Freud believed that hysterical symptoms:

The answer is enabled people to avoid unpleasant activities
Hysterical symtoms usually includes loss of hearing, suffocation, impairment of movement, uncontrollable crying, etc.
If the hysterical symtoms occur when hearing a certain type of speech for example, loss of hearing is a defense mechanism so that person shouldn't need to hear the speech that cause the hysteria.

Answer open a document;