Best Replies for d4 as black

check this: 

https://www.chess.com/forum/view/chess-openings/win-in-less-than-20-moves-with-black?page=1

And really? The Benoni? That opening is an unsound joke and you know it. If you have more than 2 braincells you beat the benoni simply by remembering to play a4 after a6 and bringing the knight from f3 to c4.

name me one opening thats flawless ? 

dont lol there aint one all openings have weaknesses

1.d4

But for real the Benoni is simply bad. The others have flaws too of course but they arent objectively bad.

btw the kna6 variant will see the a4 but in two ie a2 a3 then atfter knc7 a6 by black a3 a4 by white , two moves on a flank pawn in that line (kna6)

whats your point?

i get your idea and its bang on target re a7 a6 but not kna6-c7 then a7 a6 . not sure if it makes much difference as blacks b8 knight eats tempo too

the opening is bad and only playable at lower levels. Even there white will get the advantage if he knows a little bit of 'theory'.

just that its not an unsound joke i guess

And another thing... you suggested 1...c5 after 1.d4. This is even worse than Nf6-c5 because white can let his pawn stay at c2 and later move it to c3 to cover the d4 square which is usually weakened in the Benoni.

But it is. The Benoni is not sound. Is probably the reason why I have never seen it in any high level game. And even if there was one then it doesnt mean the opening is good.

Here is a review of the Lakdawala Slav book: "... This book is highly recommended for players from 1500 to 2300." - FM Carsten Hansen (2011)
https://web.archive.org/web/20140627104306/http://www.chesscafe.com/text/hansen151.pdf
The Lakdawala book is over 400 pages and might be a somewhat daunting project for many players. Lakdawala made some attempt to discuss how a Slav-player could adapt it for play against flank stuff. Lakdawala used an exposition based on sample games. If I remember correctly, the Soltis Career book (written in the last century) advocated a somewhat unusual line, 1 d4 d5 2 c4 c6 3 Nf3 Nf6 4 Nc3 dc 5 a4 Bg4, but perhaps the important point is that his Slav coverage was extremely brief with a focus on variations and only a very limited number of sample games. A bunch of sample games can be seen in the somewhat more recent Starting Out book by Flear on the Slav and Semi-Slav.

Glad to make U smile. There is only 1 major flaw with your logic: Indian game is the official name of 1. d4 Nf6 opening adopted by chess.com:

https://www.chess.com/explorer?moveList=d4+Nf6&ply=2

Not an expert, but I've recently switched to playing e4, partly due to problems I had countering the modern benoni.  So I think it's worth a look.

Are you insane? :D

Honestly, your answers are uneducated and reckless. The Modern Benoni is not unsound. Just because there are several variations where black can make unsound sacrifices, its plans aren't unsound. It doesn't sacrifice any material, it puts  a bishop on a great diagonal, and gets space back on the queen side. You are ridiculous with your advocacy of D4, if what you say is true all GM's would play it. Im not saying anything else is better than d4 but it is very beatable.

After d4 d5  black can opt for a Slav or Queens gambit or a London system.

Or Colle or Tarrach. etc.

After 1.d4 Nf6  black can opt for a Indian system like for example 2.c4 e6 and then 3.Nc3 Bb4 Nimzo Indian  or 3.Nf3 b6 Queen indian.   also of course he still can go for a 3...d5 and a Queens gambit

or a 3....c5 for a Benoni.   A Trompovski 2.Bg5 or a Blackmar Diemer Gambit after 2.Nc3 d5 3.e4 dxe4 4.f3  must black also have on his repetoir. And as well a Catalan after  1.d4 Nf6 2.c4 e6 3.g3 d5

or also a Benoni there is posible with 3...c5 . 

After a London system black can also play systems with d6 in stead of d5.

All and all I think  1...Nf6 is more flexible and more adventuras.

 I play Nf6.