I am required to choose 2 databases
Choose for what purpose? Assuming that you'll be a developer -and not a DBA- some of those are very similar (MySQL, Postgres and SQLServer). If you used one as a developer, you'll be able to use the other ones.
mongoDB is not a SQL DB, so that's a very different beast from a developer perspective.
SQLite is a SQL DB, but frequently used as an embedded DB (for example, on Android) - so the use cases for it are a bit different.