Which sentence uses capitalization correctly?

how did senator gutierrez vote on the new tax bill?
this summer i plan on visiting family in the northeast.
my friend has lived in north dakota for about 15 years.
a famous novel the great gatsby was first published in 1925.

This summer I plan on visiting family in the Northeast.

Explanation:

The first letter of the first word of the sentence is usually written in capital. Other parts of the sentence that needs to be capitalized are proper nouns such as specific names of people, places or things.

(B) This summer I plan on visiting family in the Northeast.

Explanation:

A topic sentence.

A topic sentence is the most important sentence in a paragraph. It is usually the first sentences in a paragraph. A topic sentence is basically the main idea of the paragraph indicating what the rest of the paragraph is going to discuss.

In this instance, the sentence, "After about two weeks, my supervisor, Ms. Banks, started assigning me more meaningful and exciting work." as the topic sentence of a paragraph indicates that the rest of the paragraph is going to further elaborate on an explain this sentence.