Answer: choice A) sine of pi/290 times x
=====================================
Work Shown:
T = Period = 580 nm
A = amplitude = 1 = vertical distance from midline to peak
B = 2pi/T = 2pi/580 = pi/290
C = phase shift = 0
D = horizontal midline = 0
..........
y = A*sin(B(x-C))+D
y = 1*sin((pi/290)(x-0))+0
y = sin((pi/290)x)
which matches with choice A
