Answer:
0.91
Step-by-step explanation:

You reflect a function with respect to the
axis by changing its sign.
In fact, if you consider the two alternatives
and 
you can see that you're choosing opposite outputs for the same inputs.
In other words, one graph will be made of points like
, the other of points like 
And the transformation

is exactly a reflection with respect to the
axis.
I think it D cause 30(cos(30x)+14=-16
Your dividing by 30
your 180 (which is degrees) is
radians. As the cosine function is periodic with period 2 we get