Question

your brain is not constantly bombarded with signals telling it that you are wearing socks. this is because the touch receptors around your ankle are
phasic receptors and fast - adapting.
phasic receptors and slow - adapting.
ton ic receptors and fast - adapting.
ton ic receptors and slow - adapting.

Explanation:

Phasic receptors respond to changes in stimuli. Since the brain isn't constantly getting signals about socks (a constant stimulus), the receptors must be fast - adapting (stop responding to constant stimuli). Tonic receptors respond continuously to stimuli, which is not the case here.

Answer:

phasic receptors and fast - adapting.