(B) Rubber
Rubber requires rainfall of more than 200 cm and temperature above 25°C, is primarily an equatorial crop, and is an important industrial raw material — all three clues match rubber.
The passage explicitly states: "It is an equatorial crop… requires moist and humid climate with rainfall of more than 200 cm. and temperature above 25°C. Rubber is an important industrial raw material." All three clues point directly to Rubber. Cotton grows in drier conditions; groundnut and mustard are oilseeds with different climate requirements.