Which is a sentence fragment?
a. a pencil, four sheets of paper, and a ruler.
b. she asked me to, so i did.
c. this morning the sunrise was spectacular.
d. we bought milk, bread, and eggs.

A. A pencil, four sheets of paper, and a ruler.

A fragment is an incomplete sentence, usually a phrase that needs another phrase to make sense. In this case, (A) is the sentence fragment, because it is just a list. It need another phrase for context.

A. A pencil, four sheets of paper, and a ruler.