After Going to a Concert, Your Hearing Is Muffled

After going to a concert, your hearing is muffled. What process may have been involved?

A) a protective increase in tension on muscles that allow movements of the ossicles (bones of the middle ear)
B) a protective increasing in the sensitivity of the cochlea to vibration
C) a protective closing of the tympanic membrane
D) a protective decrease in the potassium concentration of the endolymph
E) All of the above are true