Determine Which of the Following Are Trigonometric Identities $\csc ( \theta ) \sec ( \theta ) = \tan ( \theta )$

Multiple Choice

Determine which of the following are trigonometric identities.
I. $\csc ( \theta ) \sec ( \theta ) = \tan ( \theta )$
II. $\csc ( \theta ) \tan ( \theta ) = \sec ( \theta )$
III. $\tan ( \theta ) \sec ( \theta ) = \csc ( \theta )$
IV. $\csc ( \theta ) \sin ( \theta ) = 1$

A) II is the only identity.
B) II and IV are the only identities.
C) I, III, and IV are the only identities.
D) I is the only identity.
E) II, III, and IV are the only identities.