Teacher: In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.
Teacher: Now, understand the problem? If you are still confused, see the following example:
Passage: Nearing London, Oliver encounters Jack Dawkins, a pickpocket more commonly known by the nickname the "Artful Dodger", and his sidekick, a boy of a humorous nature named Charley Bates, but Oliver's innocent and trusting nature fails to see any dishonesty in their actions. The Dodger provides Oliver with a free meal and tells him of a gentleman in London who will "give him lodgings for nothing, and never ask for change". Grateful for the unexpected assistance, Oliver follows the Dodger to the "old gentleman's" residence. In this way Oliver unwittingly falls in with an infamous Jewish criminal known as Fagin, the gentleman of whom the Artful Dodger spoke. Ensnared, Oliver lives with Fagin and his gang of juvenile pickpockets in their lair at Saffron Hill for some time, unaware of their criminal occupations. He believes they make wallets and handkerchiefs.
Solution: Who believes Fagin's gang make wallets and handkerchiefs?.
Reason: This question is based on the following sentence in the passage "He believes they make wallets and handkerchiefs". It evaluates the understanding that the pronoun "he" refers to name "Oliver". You can ask questions like this one about most pronouns in a paragraph.

Now, solve this instance: Passage: In 2077, sixty years after a war with extraterrestrials that devastated Earth, humanity has relocated to Saturn's moon Titan via a giant space station called the Tet. Gigantic offshore fusion energy generators drain Earth's oceans to power the colonies on Titan.
Led by mission controller Sally and guided by his housemate and communications partner Victoria "Vika" Olsen, "Tech-49" Jack Harper regularly leaves his tower post to repair downed combat drones that guard the regions and generators against the alien scavengers. Although his memory has been wiped, he has had recurring dreams and visions of being on the observation deck of the Empire State Building with a dark-haired woman. He also collects the occasional artifact that he finds from humanity's past. Vika is concerned about Jack's curiosity, questioning whether they are still "an effective team," and encouraging him to do his job, so they can join the others on Titan soon.
After scavengers destroy a generator, Jack discovers that they have been using the Empire State Building's antenna to transmit coordinates to outer space. While taking a break at his secret lake house retreat, he watches a crash-landing module of a pre-war spacecraft called the Odyssey. Thinking that the ship contains aliens, he investigates, only to find humans in stasis chambers. One of the humans is the woman from his dreams. Jack protects her chamber from a drone that destroys the others, and later, revives the woman, Julia Rusakova, who makes Vika instinctively jealous. Jack and Julia return to recover her flight recorder, but are captured by the scavengers. They are taken to their headquarters at the Raven Rock Mountain Complex, and the scavengers are revealed to be human survivors.
Student:
What is the species of the beings who destroyed the generator?