TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Group 16 is called the oxygen group.

SOLUTION: Group 16 is called what?

PROBLEM: A diet rich in calcium and vitamin d may reduce the risk of osteoporosis and related bone fractures.

SOLUTION: A diet rich in calcium and what vitamin may reduce the risk of osteoporosis and related bone fractures?

PROBLEM: Certain air pollutants form acid liquid when dissolved in water droplets in the air.

SOLUTION:
Certain air pollutants form which liquid when dissolved in water droplets in the air?