The correct answer to your question is A. :)
This is caused by <span>somatosensory cortex area that used to receive input for the index
finger which severed and as a result that area is now receiving input from
the other nearby fingers casing the sensitivity to increase.
Neurons are the carriers of the feelings, pain, sensitivity etc to <span>somatosensory cortex and the served finger part's sensory feelings are being
received by nearby fingers.</span></span>
In the inner mitochondrial membrane
