Answer:
A. specialization
Step-by-step explanation:
Specialization is the factor of the agricultural sector that leads to the high efficiency of tasks performed by each sector.
The agricultural sector includes production of food grains, commercialised crops, oil seeds, poultry, dairy, fruits and vegetables and specialization in each sector develop new techniques or methods that results in the maximum efficiency in each sector of agricultural sector.
Hence, the correct answer is "A. specialization".