Primary regulator of aldosterone secretion is:
Correct option is C, Renin–angiotensin system. In Endocrinology, the accurate description is Renin–angiotensin system, and that is what you should commit to memory. Keep the definition tight and the role clear — Renin–angiotensin system is the option that correctly names the structure, process, or principle asked for in Endocrinology. Then Renin–angiotensin system is the answer you can defend. Check yourself by covering the options and writing the answer first, then matching the letter — that builds confidence. If the wording feels dense, translate it into everyday language first, then map that plain sentence back onto Renin–angiotensin system.
Ref: Animal physiology is Unit 7 of the CSIR NET Life Science Syllabus, covering core body systems. It accounts for roughly 10% of the total marks in Sections B and C.