C. would be an example of dialect.
Dialect is the sound or form of a language in a specific region. Choices A, B, and D just give words in a sentence the way they are supposed to be spelled; you can't tell how they were pronounced. Choice C changes the spelling of the words and adds apostrophes to show some of the different pronunciations in the sentence. For example, Choice C doesn't say "the", it says "th'". It gives you a clue to how it would be pronounced in this dialect.
