During repeated eruptions the summit of a volcano may be blown up leaving a large depression called:

1. Caldera
2. Hot springs
3. Geysers
4. Circum belt

Assertion (A): Most volcanic eruptions take place near plate margins.

Reason (R): When these plates slide past each other or collide against each other due to intense heat inside the earth's core, their edges produce faults along the lines of weakness.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R does not explain A.
3. A is true but R is false.
4. A is false but R is true.

Which of the following is incorrect?

1. Extinct Volcano: Mt. Kenya
2. Dormant Volcano : Mt. Kilimanjaro
3. Extinct Volcano : Mt. Etna
4. Active Volcano : Mt. Stromboli

Assertion (A): Steam is the most abundant gas that comes out of a volcano.

Reason (R): Violent eruptions, known as bombs, eject materials varying in size.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R does not explain A.
3. A is true but R is false.
4. A is false but R is true.