Given a scientific passage and an answer, generate a question for the given answer.

[EX Q]: Passage: In many ways, humans are unique among mammals. For example, we have bigger brains and a greater ability to learn than any other species in the mammalian class. In many ways, however, we are typical of the mammalian order to which we belong. That order is the Primate Order. To fully understand what it means to be human, you need to know more about this fascinating order of mammals. Answer: humans
[EX A]: What mammalian class has the greatest ability to learn?

[EX Q]: Passage: Kevin Walsh. Cows are able to digest grass with the help of the bacteria methanogens in their gut . CC BY 2.0. Answer: bacteria
[EX A]: A type of what in a cow's gut enables the animal to digest grass?

[EX Q]: Passage: Earth gets its energy from the Sun. The Sun gives off photons of energy that travel in waves. All the wavelengths of the Sun's energy make up the electromagnetic (EM) spectrum. Answer: sun
[EX A]:
Where does the earth gets its energy from?