Answer:
The correct choice is D
Step-by-step explanation:
The trigonometric functions,
and
are defined for all real numbers.
, this function is not defined where
.
, this function is not defined where
.
, this function is not defined where
.
For option A
The domain of
is all real numbers.
The domain of g(x) =tanx is 
For option B
The domain of
is all real numbers.
The domain of f(x) =csc(x) is 
For option C,
The domain of G(x) =tanx is 
The domain of f(x) =cot(x) is 
For option D;
The domain of f(x) =cot(x) is 
The domain of f(x) =csc(x) is 