Answer:
Your choice is correct.
Explanation:
The amplitude (multiplier of sin( )) is half the diameter, so is 17.5. The midline (value added to the sine function) is the difference between the maximum (50) and the amplitude (17.5), so is 50-17.5 = 32.5. All choices have the correct frequency.
The function will look like ...
f(t) = 17.5·sin(2πt/5) +32.5 . . . . . as you have marked