Best response to the Queen's Indian Defense: Kasparov-Petrosian Variation (E12)

1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. a3 Bb7 5. Nc3 · Black to move

What is the best response to the Queen's Indian Defense: Kasparov-Petrosian Variation (1. d4 Nf6 2. c4 e6 3. Nf3 b6 4. a3 Bb7 5. Nc3)? Black to move. See the top replies ranked by opening theory and real-game results, starting with Be7.

The main theoretical reply is Be7, reaching the Queen's Indian Defense: Kasparov-Petrosian Variation, Marco Defense.