Online recommendation engines typically are based on

An online recommendation engine is a set of software algorithms that uses past user data and similar content data to make recommendations for a specific user profile. An online recommendation engine is a set of search engines that uses competitive filtering to determine what content multiple similar users might like.

Explanation:

the correct answer option is b. a single paragraph.

explanation:

when you are thinking about paragraph​ topics, you should always choose a subject that can be adequately addressed in a single paragraph.

a paragraph is a piece of writing consisting of a few sentences that deal with a single theme. it has only a single idea that the paragraph revolves around and talks about.

so a paragraph topic must be chosen wisely where a single idea can be communicated in a single paragraph.

answer; organizational;