Myasthenia gravis is caused by an error in the transmission of nerve impulses to muscles. It occurs when normal communication between the nerve and muscle is interrupted at the neuromuscular junction, the place where nerve cells connect with the muscles they control.
<span>I imagine the intended correct answer here is B. Chromosomal disease. However, it is worth mentioning that the correct term to use here would be chromosomal disorder. Chromosomal disorders are usually due to either the addition or subtraction of one chromosome.</span>
<span>I would say ... C. adolescence </span>
