The correct answer is B. Mustard.
Mustard is the most important oilseed grown in Haryana. It is a major source of edible oil and is also used in the production of mustard oil cake, which is a valuable fertilizer. Mustard is a winter crop and is grown in the Rabi season. The main varieties of mustard grown in Haryana are Pusa Bold, Pusa Mustard 31, and Pusa Mustard 41.
Sesame is a minor oilseed crop grown in Haryana. It is a summer crop and is grown in the Kharif season. The main varieties of sesame grown in Haryana are Pusa 16, Pusa 21, and Pusa 24.
Groundnut is a minor oilseed crop grown in Haryana. It is a summer crop and is grown in the Kharif season. The main varieties of groundnut grown in Haryana are TMV 1, TMV 2, and TMV 3.
Soyabean is a minor oilseed crop grown in Haryana. It is a summer crop and is grown in the Kharif season. The main varieties of soyabean grown in Haryana are Pusa 216, Pusa 222, and Pusa 224.
Mustard is a better choice than sesame, groundnut, and soyabean because it is a major source of edible oil and is also used in the production of mustard oil cake, which is a valuable fertilizer.