Sorry, but I don't think you're referring to PT79 S1 Q7, which is about the journalist's argument about the mayor's boldness. If you can point me to the right question, I wouldn't mind giving my thoughts. Cheers.

The answer to your question is really contingent upon the context of 'tend to.' In a more isolated sense, I would say that phrase indicates "most." Let's say that farmers tend to receive subsidies from the government. What that really is saying is that for the most part, if one is a farmer, then one receives subsidies. So, on the flip side, that means not all farmers receive subsidies. Moreover, it's important to realize that while this relationship is not sufficient to prove causation, it is a precondition for causation. If most farmers receive subsidies, that doesn't guarantee that ALL of them do. But if all farmers do in fact receive subsidies, then it is also true that most of them do.