Answer to Question 1
xeroderma
Answer to Question 2
C
Explanation: Myasthenia gravis is due to an insufficient neurotransmitter at a synapse. Guillain-Barr syndrome is a loss of myelin covering of the nerves. Multiple sclerosis is a loss of myelin insulation around the nerves. Shingles is an eruption of painful blisters along a nerve path.