Best response to the Caro-Kann Defense (B12)

1. e4 c6 2. d4 · Black to move

What is the best response to the Caro-Kann Defense (1. e4 c6 2. d4)? Black to move. See the top replies ranked by opening theory and real-game results, starting with d5.

The main theoretical reply is d5, reaching the Caro-Kann Defense.