Answer : Option B

Explanation :

Note: Assume the total work = LCM of the given days

Take the LCM of days = LCM of (20, 30, and 60) = 60
Let the total work = 60

1 Man's one day work = 60/20 = 3 unit
1 Woman's one day work = 60/30 = 2 unit
1 The boy's one day work = 60/60 = 1 unit........................ (i)

ATQ, (2Men + 8Women + x Boy) can finish a work in 2 days.

Or, (2Men + 8women)'s 1 day work = 2 * 3 + 8*2 = 22

Or, (2Men + 8women)'s 2 day work = 22* 2 = 44
Remaining work = 60- 44 = 16
That means remaining 16 work is done by X boys in 2 days
Or, X boys' one day work = 16/2 = 8

By equation 1, 1 boy completes 1 unit work per day
So, 8 boys are required to complete 8 units of work per day.