Identify the name of crop with the given description:

a. It is primarily a crop of temperate zone.

b. Being a Rabi crop, it is mostly grown under irrigated conditions.

c. About 85 per cent of total area under this crop is concentrated in north and central regions of the country.

d. Uttar Pradesh, Madhya Pradesh, Punjab, Haryana and Rajasthan are leading producing states.

Choose the correct option from the list below.