Which word is not related to speaking?

a. avail

b. discourse

c. interjection

d. voluble

The word "avail" (a) is not related to speaking. It means to profit or take advantage of. An example of the word avail used in a sentence is:

He availed himself of the opportunity to learn from his university professor.

The words "discourse", "interjection", and "voluble" are all related to speaking; each with a different meaning. The word discourse relates to a political discussion or written or spoken communication.

The word "interjection" is used to express an emotion or sentiment on the part of the speaker. A good example is "Hey! Come back here." The interjection is the word "Hey". The word "voluble" describes a person who speaks fluently, or talks incessantly.

voluble - talkative interjection-excitement in words avail - to be useful discourse-to talk

So, your answer is a. avail