Concept:
- India has three cropping seasons: rabi, kharif and zaid.
- Kharif crops are sown with the onset of the monsoon, around June and July, and harvested in September and October. Rabi crops are sown in winter, from October to December, and harvested in summer, from April to June.
Step 1: List the main kharif crops.
Paddy, maize, jowar, bajra, tur (arhar), moong, urad, cotton, jute, groundnut and soyabean are the important crops of the kharif season.
Step 2: List the main rabi crops.
Wheat, barley, peas, gram and mustard are the important rabi crops. Any option carrying one of these cannot be an all-kharif set.
Step 3: Test each option against the two lists.
Option (A) has urad and groundnut from kharif, but gram and mustard belong to rabi, so it is mixed.
Option (B) has soyabean and bajra from kharif, but wheat and peas belong to rabi, so it is mixed.
Option (C) has maize and jowar from kharif, but mustard and gram belong to rabi, so it is mixed.
Step 4: Check the remaining option.
Option (D) lists paddy, maize, groundnut and soyabean. All four are sown with the monsoon and harvested in September and October, so all four are kharif crops.
Final Answer: (D) Paddy, Maize, Groundnut, Soyabean