Quotient means division, which is obvious by all the division answers. It says "Quotient of 4 AND ..." which means that four will be on top and everything else will be on the bottom.
So now you have: [tex] \frac{4}{?} [/tex] four over something unknown.
Reading the rest of the question, "the sum of a number and three" Sum means addition, again obvious by the answer choices. "a number" is an unknown, so we can set that to x and this x is being added to by three, so therefore x+3 would be in your denominator.
You final equation should look like this:; [tex] \frac{4}{x+3} [/tex] OR answer choice A