In this task, you are given a paragraph, and your task is to construct a question from the given passage. Construct question in such a way that (i) it is well explained in the paragraph, (ii) the words may/may not be present in the paragraph, (iii) it should start with what/how/describe. Avoid creating a question that (i) is just relevant to one or two sentences, and (ii) not relevant to passage. 
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Question: A frog lays eggs in the water. Tadpoles develop inside of the eggs. The eggs hatch. The tadpoles eat and grow. The tadpoles grow legs and form into frogs. The frogs leave the water. 

Answer: Describe the life cycle of a frog


Question: Bacteria enters the body. Bloodstream. Cells in the body are attacked. Cells are killed. Different kinds of sickness are formed. 

Answer: How does a virus cause disease?


Question: The air is cold. Water is in the air. The water forms tiny ice crystals. The ice crystals collide with each other. The ice crystals stick to each other. The ice crystals get bigger as more of them stick together. The ice crystals get too heavy to be in the air. The ice crystals become snowflakes. The snow flakes fall to the ground as snow. 

Answer:
How does snow form?