6) E

Most efficient way: make equations.

Equation for Cl

b = a + 2a + 2y

b = 3a + 2y

Let us check which of the options can satisfy the equation above.

A – Wrong

8 ≠ 3 + 6

B – Wrong

8 ≠ 3 + 8

C – Wrong

4 ≠ 3 + 2

D – Wrong

16 ≠ 6 + 12

E – Correct

16 = 6 + 10