Using who? or what? instead of which?

Using who? or what? instead of which?

Don’t Say:
Who of the two boys is the taller?

Say:
Which of the two boys is the talier?

Note:
The interrogative pronoun what? doesn’t imply choice What’s your telephone number? it’s also used to ask for a person’s profession, What’s your father? – He’s a lawyer. Use the interrogative pronoun which? for both people and things, ask for one out of a definite number.