Scientists rely on concepts when researching crop production and medicine. biology physics geology astronomy

A). Biology.

Explanation:

As per the question, scientists depend on 'biology' concepts at the time of researching on medicine and the crop production as the biological concepts assist the researchers to test the validity of their experiments and their results. The medicinal researches as well as agriculture both are either directly or indirectly associated to the biological systems or its derivatives. Thus, 'biotechnology' is used for modification and advancement in their respective fields and hence, option A is the correct answer.