The correct option is C 5
To find the maximum length, we need to find the H.C.F. of 10 and 25.
First let's list down the factors of 10 and 25.
Factors of 10: 1, 2, 5, 10
Factors of 25: 1, 5, 25
Common factors of 10 and 25: 1 and 5.
Therefore, the H.C.F. = 5
Therefore, the maximum length of each piece should be 5 m.