Correct option is A
SOLUTION:
The no which will divide 39 and 84 so as remainder 3 in each case.
This means that if we subtract 3 from both 39 and 84, the resulting numbers (36 and 81) must be perfectly divisible by the desired number.
Now, we need to find the greatest common divisor (GCD) of 36 and 81.
The GCD of 36 and 81 is 9.
Therefore, 9 is the greatest number that divides 39 and 84, leaving a remainder of 3 in each case.
So, the answer is 9