A branch of biology that deals with structure and function of cells is called:

Explanation: Correct Answer: Cytology is the branch of biology that deals with the study of cells, including their structure, function, and chemistry. It is crucial in understanding cell life cycles, physiology, and pathology. Other Options: (A) Semiology - This is the study of signs and symbols, particularly in language. (B) Oncology - This is the branch of medicine that studies cancer. (D) Lithology - This is the study of the physical characteristics of rocks.