Answer:
A)
But really there is no effect since cos(-x)=cos(x).
Step-by-step explanation:
Cosine is an even function.
Even functions are symmetric about the y-axis.
So really for cosine; cos(-x) has no change to cos(x) since they are equal.
But if you keep in mind that cosine is symmetric about the y-axis, then it has been reflected over the y-axis; this is the vertical axis.
A)
