Answer:
Third choice
Explanation:
The domain of f(x) is the set of all real values except 7, i.e

and the domain of g(x) is the set of all real values except -3, i.e

The domain of
is the set of all real numbers x in the domain of
such that
is in the domain of
.
However any numbers that are excluded from the domain of f must also be excluded from the domain of
.
Therefore the correct choice is all real values except x=7 and the x for which f(x) =7