Teacher: 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. 
Teacher: Now, understand the problem? If you are still confused, see the following 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. 
Solution:  What causes a volcano to erupt? 
Reason: 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.

Now, solve this instance: You speak into the receiver on your phone. Sound waves move parts inside the receiver. Movement causes the magnet inside to produce eletricity. Electricity is transferred through  a wire or cable. A membrane in the other persons phone is vibrated by the magnet in their telephone. Sound is produced. They hear you. 
Student:
Describe how a message travels from one person to another over via telephone