Answer:
B. 16.7
Explanation:
The mnemonic SOH CAH TOA reminds you that the relationship between the side adjacent to the angle and the hypotenuse involves the cosine function:
Cos = Adjacent/Hypotenuse
Filling in the numbers from your diagram gives ...
cos(50°) = x/26
Multiplying by 26 gives x.
x = 26·cos(50°)
x ≈ 16.7