Answer:
a. islands in the Pacific Ocean.
Explanation:
A volcanic belt is a large region of intense volcanic activity.
We can clearly see that volcanic belts are regions where volcanic activity is maximum. Volcanic belts are characterized by eruptions of gases, ash, rock, lava etc.
Such eruptions push magma to the earth's surface at high temperature. The area around the Pacific that is prone to volcanic activities is generally referred to as the 'ring of fire'.