Assertion (A) Cu2+ iodide is not known.

Reason (R) Cu2+ oxidises I- to iodine.

1.  Both assertion and reason are true, and the reason is the correct explanation of the assertion.

2.  Both assertion and reason are true but the reason is not the correct explanation of assertion.

3.  Assertion is not true but the reason is true.

4.  Both assertion and reason are false.

Hint: Cu2+ oxidises I- to iodine.
 
Iodide ions are strong reducing agents. Therefore, Copper (II) Iodide is converted into Cu2I2 and I2.  Cu2+ oxidises I- to iodine is also a correct explanation
 
2CuI2Cu2I2 + I2
 
Hence, both assertion and reason are true, and the reason is the correct explanation of the assertion.