Directions: The first and the last sentences of the passage are numbered 1 and 6, respectively. The rest of the passage is split into four parts A, B, C and D. These four parts are not given in their proper order. Read the sentences and find out which of the following combinations is correct.

1. There are different ways in which volcanoes are classified. A. The difficulty with this is that man has been on the planet for a relatively short period of time and our historical records are rather an inaccurate predictor of volcanic activity as dormant, and even extinct volcanoes have been known to erupt. B. This classification is problematical as there is no clear definition of what makes a volcano active, dormant or extinct. C. Typically, a volcano is said to be extinct if it has not erupted in historical times or at least since written records began, and it is dormant if it is known to have erupted in historical times, but is now quiet. D. Perhaps the most common and certainly the one used by non-specialists is the division of volcanoes into the categories of active, dormant or extinct.
2. This can be exemplified by one of the most notorious episodes in the annals of vulcanology, the eruption of Mt. Vesuvius in 79 AD.