Answering the wrong IELTS essay question

The IELTS Task 2 writing question can be very challenging. Not only is it a test of your grammar and vocabulary, it also tests your ability to analyze and answer the RIGHT question.

Students can sometimes write well on a topic but get a low score. This is usually because they are answering the WRONG question within the topic presented to them.

This is a real example from an essay a student gave me before we started his course.

Question
Using a computer can have more negative effects than positive effects on your children. Do you agree or disagree?

2nd para
Some people believe that it is antisocial to be seen using your computer every day by your children. It is thought that this attitude can rub off on children and for them to copy a parent’s actions as they grow up.
 
Can you spot the mistake?