Q.

Assertion (A): 6n never ends with the digit zero, where n is natural number.
Reason (R): Any number ends with digit zero, if its prime factor is of the form 2m×5n, where m, n are natural numbers.

1 Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).  
2 Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).  
3 Assertion (A) is true but Reason (R) is false.  
4 Assertion (A) is false but Reason (R) is true.  

Ans.

(1)

Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).

6n=(2×3)n=2n×3n , Its prime factors do not contain 5 i.e., of the form 2m×5n,

where m, n are natural numbers. Hence, 6n never ends with the digit zero.