Answer:
? = A) 4
Explanation:
If we notice line FG and QR are similar.
FG = 24 and QR = 8. The relationship between the the two sides is that FG is 3 times more than QR ---> 8 x 3 = 24.
This relationship is true for the rest of the triangles since they are stated to be similar:
FG = 3(QR)
24 = 3(8)
EG = 3(6)
18 = 3(6)
Finding PQ:
EF = 3(PQ)
12 = 3(?)
? = 4
Therefore, the unknown side is 4.