Select the correct option based on statements below:
Assertion (A): Nickel can be purified by Mond’s process.
Reason (R): It is a volatile compound that decomposes at 460 K to give pure Ni.
  
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.