The answer would be A. whose
B. who's would not make sense in this situation because who's is a contraction which means 'who is'. If that was to be used in the answer, the sentence would be, "Margaret wants to knwo<em> who is</em> bike this is," which makes no sense whatsoever
Whose shows possession
Hope my answer helped! :)
We use pronouns so that we are not repetitive.
Answer: A) or the first option.
A pronoun is really a word that takes the spot of a noun, without pronouns sentences really wouldn't make sense or be clear here are examples.
Deaththekid101 answered a question
He answered a question
The spider is crawling
It is crawling
Zaxby's is the best resturaunt
This is the best resturaunt
See? pronouns take places so its important we have them.
What are you talking about is this supposed to be English