Which of the following voices is likely to have minimum frequency.

(a) A man (b) A baby girl (c) A baby boy (d) A woman

Answer- a) A Man

Frequency Is Directly Proportional To Pitch

Pitch Is Directly Proportion To Softness

Less Pitch Hoarse Voice 

According To The Giving Options Man Is Correct

a man

(c) A man

The voice of an adult man is of lower pitch in comparison to the voices of a baby boy, a baby girl and a woman. Since frequency of a sound is directly proportional to its pitch,so,  man voice is of minimum frequency in comparison to a boy, a girl, or a woman voice.