(b) NEAT
NSE's trading system is called NEAT — National Exchange for Automated Trading. It is a state-of-the-art, client server based, fully-automated screen based trading system.
The passage explicitly states: "Its trading system, called National Exchange for Automated Trading (NEAT)…" BOLT is the BSE trading system. Examiners expect you to know the full form as well, since it may appear as a 1-mark or 2-mark question.