Capitalization and the correct use of punctuation, especially when using parenthesis, is vital for the correct meaning and idea of a sentence to be communicated to the reader or listener. When using parenthesis, particularly, one thing to keep in mind is that the purpose of this technique is to expand on information on a sentence, or to clarify information that may not be vital to the sentence. Basically, it can be understood as a footnote. However, the wrong use of punctuation within one or outside of it may mislead a reader and the wrong use of capitalization can also mislead. Remember that capitals are used for the proper names of objects, people or even events that are important, otherwise, they must not be used. A parenthesis, also, is not a period, therefore, capitals must not be used within them unless there is a proper name used within them. If within a parenthesis you use a period, like in example A, the reader understands that the idea has ended, and that between the sentence before the parenthesis and the sentence after the parenthesis, the ideas are not connected, which is not the case. This is why the correct answer C.
