D. 2(x + 4)
Now you get that answer by working the problem. For instance, Kailey plays x hours per month, so we get
K = x
Now Trent plays 4 more hours than Kailey, so we get
T = K + 4.
Since we know that K = x, we can substitute x for K and get
T = x + 4
Now Megan plays two times as much as Trent. So we get
M = 2T
But since T = x + 4 we can subsitute x + 4 for T, getting
M = 2(x + 4)
We need the parenthesis because multiplication has a higher priority than addition and without the parenthesis the multiply by 2 wouldn't have affected the addition of 4.