A metal rod of uniform thickness and of length `1m` is suspended at its `25cm` division with help of a string. The rod remains horizontally straight when a block of mass `2kg` is suspended to the rod at its `10cm` division. The mass of rod is
A. `0.4 kg`
B. `0.8 kg`
C. `1.2 kg`
D. `1.6 kg`