Which part of neuron is the trigger zone for action potential initiation?
Axon hillock–initial segment junction (B) is the right choice. This sits at the heart of Neuron; Structure and Function: the wording points straight to what is happening in the tissue or organ system. A useful study habit is to ask what the structure or process is for: Axon hillock–initial segment junction is the option that correctly names the structure, process, or principle asked for in Neuron; Structure and Function. That reasoning supports Axon hillock–initial segment junction. One solid sentence about why this works is enough for recall — you do not need a long essay for every MCQ.
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.