Synaptophysin is best described as:
Correct option is C, Structural vesicle membrane protein. In Synapse, the accurate description is Structural vesicle membrane protein, and that is what you should commit to memory. Keep the definition tight and the role clear — excitable-cell physiology turns on membranes, ions, and signalling steps, and Structural vesicle membrane protein captures the correct piece of that story. Then Structural vesicle membrane protein 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 Structural vesicle membrane protein.
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.