Option 1 -> Salivation on seeing food is an involuntary reflex action controlled by the autonomic nervous system.
Option 2 -> Immediate hand withdrawal from hot surface is a classic spinal reflex that occurs without conscious thought.
Option 3 -> Quick withdrawal from extreme cold is also a protective spinal reflex action.
Option 4 -> Smelling smoke and running away requires conscious recognition of danger, decision-making, and voluntary motor control to execute running.
Hence, Option 4 -> This involves complex cognitive processing (identifying smoke as danger), conscious decision-making (choosing to escape), and voluntary motor actions (running). Unlike true reflexes which are automatic and involuntary, this is a deliberate response that requires higher brain center involvement -> correct