Use Socratic to get the answer to your question
For this item, the most probable answer is letter A. One of the most important reason why Earth is a livable place is its proper distance from the Sun which gives adequate temperature and amount of radiation. Other factors are the gravity, atmosphere, and water.
b. small buisnesses find it harder to compete
This is actually a Maths question - although is it related to geography.
In order to calculate this, we simply need to find out how many is 80% of 1500, like this:

So the answer is: 120 volcanoes are located in this area!