Option 1 -> The passage explicitly states "the animal itself has come to symbolise a dimwit, someone of little value" - so donkeys ARE commonly accepted as dimwits.
Option 2 -> The passage begins with "Donkeys may be the proverbial beast of burden" - clearly indicating they ARE commonly accepted in this role.
Option 3 -> The passage makes no reference to donkeys being considered parasites. In fact, it highlights their positive contributions like maintaining grassland ecosystems and having a low environmental footprint.
Option 4 -> The passage mentions donkeys symbolize "someone of little value," implying they ARE commonly perceived as useless.
Hence, Option 3 (a parasite) -> The passage discusses common negative perceptions of donkeys (dimwit, beast of burden, little value), but never mentions them being viewed as parasites. Rather, the text emphasizes their beneficial qualities and sustainable contributions to farming and ecosystems -> correct