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. 

Let me give you an example:  Magma rises from deep in the earth. The magma goes into volcanos. The volcanos pressure the magma upwards. The pressure causes the magma to push through the surface of the volcano. The lava cools. The lava forms new rock. New magma is pressured to the surface of the volcano. The volcano bursts through the rock the formed after the last eruption. 
The answer to this example can be:  What causes a volcano to erupt? 
Here is why: The process paragraph explains in steps about - the cause for volcano eruption. The keywords in the question are relevant to the process paragraph given. So, this is a good question.

OK. solve this:
The virus finds an animal cell. The virus attaches to the cell's surface. The cell swallows the virus. The virus' RNA is released into the cell. The cell mistakenly reads the virus' RNA instead of its own. The cell creates new viruses. The animal cell releases the new viruses. The new viruses can infect more cells. 
Answer:
How does a virus infect an animal?