Sun rises in east, doesn't it?

Here's why:

* The statement is positive: "Sun rises in east" is a positive statement.

* The tag question is negative: We use "doesn't it" to create a negative tag question.

* The verb in the tag question matches the main verb: The main verb is "rises", so the tag question uses "doesn't".

* The tag question uses the correct pronoun: The subject of the statement is "Sun", so the pronoun in the tag question is "it".