Which of the following is the correctly punctuated sentence?

• A. Its a sunny day.
• B. Its' a sunny day.
• C. It's a sunny day.
• D. Its is a sunny day.

Answer: (C)

The correctly punctuated sentence is "It's a sunny day." This is because "It's" is a contraction of "it is," which is the appropriate usage in this context. The apostrophe is essential here as it indicates that letters have been omitted to form the contraction.

In contrast, the other options lack proper contraction usage. The first option "Its a sunny day" is incorrect because it does not use the contraction and fails to convey the intended meaning. The second option "Its' a sunny day" incorrectly adds an apostrophe after "Its," which is not standard English and suggests possession rather than the contraction "It is." Lastly, "Its is a sunny day" is incorrect because it uses "Its" without the apostrophe when it should be using "It's" as a contraction for "it is." This highlights the importance of understanding contractions and their appropriate punctuation in English grammar.