In your family, has lived on a farm? which pronoun correctly completes the sentence?

Who

Explanation:

 The pronoun who correctly completes the sentence. "In your family, who  has lived on a farm?"  The sentence is a question (what person has lived on a farm? ), so the correct word is the pronoun who , which is the subject also. The verb that follows it is an affirmative verb (although it is an interrogative) has lived . Attention: We use interrogative verb in cases like these: Who are you? Who are those boys?