The correct option is A 0.5, 0.75, 0.25
The units are shown by different levels of flasks where one unit is one block; two units are two blocks and so on. Each of the three flasks is divided into 4 levels. Flask A is 24 (two-fourth) filled with water, which becomes 12= 0.5, flask B is 34(three-fourth) filled with water, which becomes 0.75 and flask C is 14(one-fourth) filled with water, which becomes 0.25.