if white pushes the e pawn to e5, black has the option of playing Bf5 or c5. it is a matter of taste as to which one they choose. But both lead to different variations of the Advanced Caro Kann. white must know these lines too.
What is the best response to scandinavian?

But the best way is either taking the pawn or transposing into the blackmar-diemer gambit

i have winning stats with the gedult BDG. everyone else does better with the 3.Nc3 main line. I'm guessing a lot of players maybe studuied the main line, or it's that thing where I tend to do bad in lines where knight to c is the first piece play

Above about the 1700 level, the move I've heard Scandi players say they hate the most is 3.Nf3 (whether black plays 2...Qxd5 or Nf6). That includes me. It's very solid line for white, but takes all the fun out of it, like the stuff you get after 2...Qxd5 3.Nc3. I play both sides of the Scandi, and with the white pieces I usually go Nc3 to avoid the snooze-fest you can get after 2...Qxd5 3.Nf3 Bg4 4.Be2.
When I play the Scandinavian as black I hate players who:
1.develop all the minor pieces except the b1 knight
2.castle
3. play c4 and only after play Nc3
4.develop their queen and then plant the f3 knight on e5
But the best way is either taking the pawn or transposing into the blackmar-diemer gambit
That's because I transpose into tennison and sometimes they fall for icbm, and I learnt that tennison is a bad way to play against scandi

The main line exd5 Nc3 is best by a mile. It's the only one that gives white prolonged advantage. Everything else gives black quite a bit of play. Some of the gambits are decent gambits, by why play a decent gambit against a tier 2 defense? Similarly Nf3 is a respectable move, but after Bg4 black gets a quick queenside castle and you've turned your advantage into a pretty even game.
2. e5 in particular is a disaster. Gives the Scandi player a tempo up advanced caro/ bishop out advanced French. After 2.c5 the engine is already screaming 0s, which is not what white wants out of the opening.

Above about the 1700 level, the move I've heard Scandi players say they hate the most is 3.Nf3 (whether black plays 2...Qxd5 or Nf6). That includes me. It's very solid line for white, but takes all the fun out of it, like the stuff you get after 2...Qxd5 3.Nc3. I play both sides of the Scandi, and with the white pieces I usually go Nc3 to avoid the snooze-fest you can get after 2...Qxd5 3.Nf3 Bg4 4.Be2.
Nc6 O-O-O e5 is pretty fun. You won't hate Nf3 so much after that.

Above about the 1700 level, the move I've heard Scandi players say they hate the most is 3.Nf3 (whether black plays 2...Qxd5 or Nf6). That includes me. It's very solid line for white, but takes all the fun out of it, like the stuff you get after 2...Qxd5 3.Nc3. I play both sides of the Scandi, and with the white pieces I usually go Nc3 to avoid the snooze-fest you can get after 2...Qxd5 3.Nf3 Bg4 4.Be2.
Nc6 O-O-O e5 is pretty fun. You won't hate Nf3 so much after that.
Looks interesting! I'll give it a try.

The best response to Blacks' d5 is Nc3, polite suggestion to take up checkers instead and resign (as white).
Nc3 is feeble at hands equality to black
a reverse kings indian does look fun tho

The main line exd5 Nc3 is best by a mile. It's the only one that gives white prolonged advantage. Everything else gives black quite a bit of play. Some of the gambits are decent gambits, by why play a decent gambit against a tier 2 defense? Similarly Nf3 is a respectable move, but after Bg4 black gets a quick queenside castle and you've turned your advantage into a pretty even game.
2. e5 in particular is a disaster. Gives the Scandi player a tempo up advanced caro/ bishop out advanced French. After 2.c5 the engine is already screaming 0s, which is not what white wants out of the opening.
I DESPISE 2.e5! It., and the being stuck with the stonewall, with NO known tactical replies to 1.d4 that DON'T involve loathesome fianchettos, with no amateur games to data dump or acceptable way to create tree based books and study them, were the reasons I quit chess for a decade or more and only played tactics puzzles which is all chess it to me, really.
I don't like ANY line in the marshall. even good old scandinavian gambit's had all the fun taken out of it now that everyone knows to pavnov. I REALLY hate 3.d4 too. i don't play portugese
it's maddening when you're stuck with an entire side of the board's repertoire you despise and have no easy way out of. the ONLY line I like to play as black (and i actually do have a winning scandinavian record overall) is the englund hartlaub/charlick gambit. that's it.
getting stuck playing black 2+ times in a row, or facing numerous punk cowards who won't rematch my 1.e4 trigger my PTSD big time.

i think the blackmar-deimer gambit!
The downside is you have to learn a variation of the french and the caro cann.

I DESPISE 2.e5! It., and the being stuck with the stonewall, with NO known tactical replies to 1.d4 that DON'T involve loathesome fianchettos, with no amateur games to data dump or acceptable way to create tree based books and study them, were the reasons I quit chess for a decade or more and only played tactics puzzles which is all chess it to me, really.
I don't like ANY line in the marshall. even good old scandinavian gambit's had all the fun taken out of it now that everyone knows to pavnov. I REALLY hate 3.d4 too. i don't play portugese
it's maddening when you're stuck with an entire side of the board's repertoire you despise and have no easy way out of. the ONLY line I like to play as black (and i actually do have a winning scandinavian record overall) is the englund hartlaub/charlick gambit. that's it.
getting stuck playing black 2+ times in a row, or facing numerous punk cowards who won't rematch my 1.e4 trigger my PTSD big time.
Me:
what about the blackmar diemer?
I think its really annoying and i hate it