Question

Which polynomial expression represents the area of the outermost square tile, shown below?

Answer 1

Funny enough, it is the one that you clicked on. the of the square simple needs to be squared to find the answer. 
I hope this helped. 

Answer 2

By definition, we have that the area of a square is given by:
 $A = L ^ 2$
 Where,
 L: square side
 We have that the side of the square is given by:
 $L = x + 3$
 Substituting values:
 $A = (x + 3) ^ 2$
 Rewriting the expression we have:
 $A = x ^ 2 + 6x + 9$
 Answer:
 The area of the outermost square tile, shown below is:
 $x ^ 2 + 6x + 9$