what should be the minimum value of x for which (80!)/x will not be divisible by 4?
a)80
b)4*6*8........*80
c)2*3*.......*80
d)7686e)None of these

Option b

I could't get your solution. What actually is asked in the question?

The denominator is 4. The smallest number for which 80! will not be divisible by 4 will be smallest prime greater than 80. Th smallest prime number greater than 80 is 83. So the correct answer should be none of these.