Which sentence uses "it's" correctly?

Which sentence uses "it's" correctly?

• A. Its a sunny day.
• B. Its' going to be fine.
• C. It's sunny outside.
• D. It's dog is barking.

Answer: (C)

This item tests the difference between it's and its. When you mean it is, you use the contraction it's. When you mean something belongs to it, you use its with no apostrophe.

So the sentence that correctly uses a contraction is the one that expands to it is sunny outside. The others go wrong by either omitting the needed apostrophe, placing an apostrophe where there isn’t one, or using a possessive where a contraction is meant: its without an apostrophe isn’t correct here, its’ is never correct, and using it's with “dog” makes the phrase ungrammatical.