Frequency of eruption serves as the basis of classification of volcanoes. Which of the following is not in this category?
An active volcano is a volcano that has had at least one eruption during the past 10,000 years. An active volcano might be erupting or dormant.
An erupting volcano is an active volcano that is having an eruption...
A dormant volcano is an active volcano that is not erupting but supposed to erupt again.
An extinct volcano has not had an eruption for at least 10,000 years and is not expected to erupt again in a comparable time scale of the future.
The above classification is based on the frequency of eruption while the classification as a composite volcano is based on the structure of the volcano thus option C is the right answer.