Which one of the following number can be removed from the set S=[0,2,4,5,9] without changing the average of set 5?

S=[0,2,4,5,9]
Average=Sum of Terms/Number of Terms
Sum of Terms=0+2+4+5+9=20
Number of Terms=5
Average=20/5=4
Now
Remove one number=4
Sum of Terms=0+2+5+9=16
Number of Terms=4
Average=16/4=4