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

Ex Input:
Passage: Oxygen is needed to make ozone. Ozone is a molecule made of three oxygen ions. Ozone in the upper atmosphere blocks harmful solar radiation from reaching the surface. Without oxygen, life on Earth would have been very simple. Answer: three

Ex Output:
How many oxygen ions make up an ozone molecule?

Ex Input:
Passage: 19.3 The Human Population Earth's human population is growing exponentially. Humans have increased their carrying capacity through technology, urbanization, and harnessing the energy of fossil fuels. The age structure of a population allows us to predict population growth. Unchecked human population growth could have dire long-term effects on human welfare and Earth's ecosystems. Answer: carrying capacity

Ex Output:
Human population is growing exponentially and humans have increased what normally limiting factor through technology, urbanization, and harnessing the energy of fossil fuels?

Ex Input:
Passage: The genetic code is the same in all living things. This shows that all organisms are related by descent from a common ancestor. Answer: genetic

Ex Output:
What code is the same in all living things and shows that all organisms are related by descent from a common ancestor?