The width of synaptic cleft in chemical synapse is approximately:
Correct option is C, 20–50 nm. In Synapse, the accurate description is 20–50 nm, and that is what you should commit to memory. Keep the definition tight and the role clear — 20–50 nm is the option that correctly names the structure, process, or principle asked for in Synapse. Then 20–50 nm 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 20–50 nm. Remember that physiology questions reward precise language: name the process, the location, and the outcome, then match that to the option text.
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.