Identify Which Revision of the Following Sentence Is Correct: My

Multiple Choice

Identify which revision of the following sentence is correct: My sister is an RN, but it doesn't interest me.

A) My sister is an RN, but I'm not interested in it.
B) My sister is an RN, but this doesn't interest me.
C) Either A or B can be correct depending on the intended meaning of the sentence.
D) Neither A nor B is correct.