Answer:
D
Explanation:
Convert all of the fractions' denominators so that they are 8. This is because 4,2, and 8's least common multiple is 8.
Remember that when multiplying the denominator, we must also multiply the numerator. So:


Since we are asked to add all of them, we can do that easily since all of the fractions now share a common denominator.

Therefore, the answer is D.