Answer:
Option A, Anesthesiologist
Step-by-step explanation:
Anesthesiologist is a doctor who practices anesthesia. He/she is a specialized doctor or MD who practices anesthesia and several other medical services such as preoperative care.
He is the one responsible for developing anesthesia plan and then also administers anesthesia.
This person must gave gained knowledge in the field of anesthesia and research associated with this field and thus is solely responsible for the safety of patient during surgery
Hence, option A is correct