**Choices: **

A. 4 ft

B. 3.5 ft

C. 3 ft

D. None of the above

**Correct Answer: A**

**Solution:**

**Step 1: ** Let *h* be the height of the boy.

**Step 2:** ΔACE ~ ΔBCD, because the measure of angle EAC = measure of angle DBC and the measure of angle C = measure of angle C.

**Step 3: ** Corresponding sides of similar triangles are proportional.

**Step 4:** The proportion here is:

**Step 5:** 160(*h* + 80) = 168 × 80

[Write the cross products.]

**Step 6:** 160*h* + 12,800 = 13,440 [Multiply.]

**Step 7:** 160*h* = 640 [Simplify.]

**Step 8:** *h* = 4 [Divide both sides by 160 and Simplify.]

** Step 9: ** So, the height of the boy is 4 ft.