Notice that the graph of f(x) includes the point (10,1), after applying each listed transformation to (10,1), we get

Thus, g(x) is a reflection across the y-axis of f(x).
The answer to 7) is option D.
8)
In general, a reflection across the y-axis is given by the transformation below

Therefore, in our case,

The answer is g(x)=log(-x), option C.