Myasthenia gravis: - chronic condition where nerve impulses are not properly transmitted to the musclesb- leads to progressive muscular weakness and paralysis, if it affects respiratory muscles, it can be fatalc- cause is unknown, but thought to be autoimmuned- no cure, treatment is supportive

B- leads to progressive muscular weakness and paralysis, if it affects respiratory muscles, it can be fatal

Explanation:

Myasthenia Gravis is a term originated from Greek word  and Latin word, With Myasthenia coming from a Greek word which is further slipt into two: 'Mys' meaning muscle and 'astheneia' meaning weakness. 'Gravis' on the other hand is a Latin Word meaning serious.

Myasthenia Gravis is an autoimmune neuromuscular disease that affects the skeletal muscles leading to muscle weakness and paralysis, it effect is relative which can vary from mild to severe(fatal). It is capable of affecting the muscles of the eyes, face (by the emergence of droopy eyelids and mouth) and respiratory muscles.

This is because the muscles of the respiratory system (specifically the diaphragm (is a thin skeletal muscle that sits at the base of the chest and separates the abdomen from the chest)) participate actively in inhalation and exhalation by assisting in expansion and contraction of the thoracic cavity (chest cavity).

It can be treated by a medical practitioner with  medication (drugs) or by surgery.

Hence, from the aforementioned, Myasthenia Gravis  leads to progressive muscular weakness and paralysis, if it affects respiratory muscles, it can be fatal.

are there any letter choices to this or is this an open ended question?

no. i had a handful this morning