The correct answer is To interact with readers by soliciting their viewpoints.
Step-by-step explanation:
A poll is an instrument used to collect the opinions of a group of people. In this, people select one option or point of view from a set of different options to show their specific perspective. For example, in a poll about elections people select the candidate they most support. In this context, by including a poll in a blog the author of the blog can interact with readers and know their viewpoints about a specific topic. According to this, the best reason for a blog is "To interact with readers by soliciting their viewpoints."