Answer:
C) 4
Explanation:
The given function is

The function is defined on two intervals.
The first interval is
and the second interval is
.
does not belong to any of these intervals.
does not also belong to any of these intervals.
belongs to the interval
.
Hence 4 is in the domain of f(x).
does not also belong to any of the intervals.
Therefore the correct answer is C.