Concept:Agronomy is the branch of agricultural science that deals with crop production and soil management.
Explanation:Agronomy centres on the relationship between field crops and the soil.
It covers seed selection, planting methods, crop rotation, irrigation, and tillage.
It also includes soil fertility and fertiliser use.
The main goal is to obtain high crop yields without damaging the soil.
Option B is wrong because animal breeding belongs to animal science.
Option C is wrong because farm machinery belongs to agricultural engineering.
Option D is wrong because plant disease and pest control belong to plant pathology.
Only Option A correctly combines crops with soil management, which is the exact scope of agronomy.
Answer:A. The study of crop production and soil management