In the following question, a statement of assertion followed by a statement of reason is given. Choose the correct answer out of the following choices:

Assertion : Zone refining method is very useful for making semiconductors .

Reason : Semiconductors are of high purity. 

Both assertion and reason are true but the reason is not the correct explanation of the assertion.

Zone refining method is very useful for producing semiconductors because the impurities present in semiconductors are more soluble in the melt than in solid state of the metal.This method is useful for producing semiconductors of very high purity.
Hence, both assertion and reason are true but reason is not the correct explanation of assertion.