Voice of which of the following is likely to have a minimum frequency?

The correct option is C

A man

The explanation for the correct option:

1. The frequency of a sound is proportional to its pitch.
2. An adult man's voice has a lower pitch than the voices of a baby boy, a baby girl, and a woman. So a man has a minimum frequency.
3. Among this group, a baby girl's voice has the highest pitch.
4. Pitch is the characteristic of sound that distinguishes an acute (or shrill) note from a grave or a flat note.
5. A higher frequency note has a higher pitch than a lower frequency note.

Hence, Option(C) is correct.