When asking a question, how does a person’s voice change?
a.
a person will often increase volume when asking a question.
b.
a person will often change the pitch of their voice when asking a question.
c.
a person’s voice does not usually change when asking questions.
d.
a person is likely to lower their volume when asking a question.

The correct answer is B: A person will often change the pitch of their voice when asking a question.

Explanation:

When we ask questions, we usually change the intonation, this is the pitch of our voice. In most world languages, intonation determines the meaning of the sentence. For example, a pitch of our voice can reveal our current mood (anger, irony, happiness...) and change the context of the sentence, regarding the tone we are using.

For example, if we change the intonation in the following sentence, it could be considered as a question.

e.g. You don't want to sit with us.

If we change our intonation, this statement could be interpreted as a question which implies surprise or unexpected outcome.

e.g. You don't want to sit with us?