If 5 persons can do 5 times of a particular work in 5 days, then, 7 persons can do 7 times of that work in?  Select the correct option:
A) 3 days
B) 4 days
C) 5 days
D) 7 days
E) 8 days
That is, 1 person can do one time of the work in 5 days.   Therefore, 7 persons can do 7 times work in the same 5 days itself   5 days)
<result>C</result>
If 5 persons can do 5 times of a particular work in 5 days, then, 7 persons can do 7 times of that work in?