Hope this helps but try to do process of elimination.
Answer:
The answer to your question is below
Step-by-step explanation:
csc α - cot α = 
Work with the left part

Simplify

Multiply by the reciprocal
Simplify

Remember that
sin²α = 1 -cos²α
Substitute the previous equation

Simplify
The identity i proved.
Solve each one to find that D is the answer
What
ask the question I will answer it
go ahead ask