Assertion and Reasoning:
Assertion (A): Combustible substances catch fire only when they reach their ignition temperature.
Reason (R): Ignition temperature is the minimum temperature required to initiate combustion without an external source of ignition.
1
Both A and R are true, and R is the correct explanation of A.
2
Both A and R are true, but R is not the correct explanation of A.
3
A is true, but R is false.
4
A is false, but R is true.