'rentrer" can mean "put in" or "enter"
OK, that's not a question. So, the system presents "rentrer" as a new word with a meaning of "to put in" and if you use the drop down list as "to bring". Now the system knows that "rentrer" also means "to enter" as well, but does't share this information about this other form of this verb so I, not wishing to double guess the system, translate "je rentre" as "I put" even though I know that it should probably be "I enter" . Does the system tease people?
Well, the system seems highly automated in that it will take a single translation and reform it into different types of questions, or reuse it for different skills. Unfortunately this often leads to bizarre situations if a word has multiple meanings - confusing the reader more often than not.
I assume in your case though, it would probably have accepted "I enter" also.
I would have translated "rentrer" as 'to return', but none of the translations given by the system were anywhere near to "to return", so I lost my nerve and used only one of the definitions given by the system.
I can't find anything in Larousse that suggests that "rentrer" means "to put on", but maybe if you think of "Je rentre dans ma chemise" as "I get into my shirt" it makes a bit more sense. It seems that's really pushing it, though,