(a) The same kind of plants grown and cultivated on a large scale at a place is called crop.
It means the same type of plants that is cultured using various tools, techniques and treatments using organic and inorganic nutrients during agriculture on a large field, this group of plant is called as crop.
For e.g., during rice cultivation, many rice plants are grown and cultivated together and thus rice plant is an example of crop. Similarly when a particular vegetable is grown in large quantity then it's plants are called as crop.
Other examples of crop are wheat plants, oats, millets, fruits etc.
Cultivation is the process of nurturing and nourishing the crops with manure which are organic compounds providing organic nutrients and fertilizers which are inorganic compounds providing inorganic nutrients.