The correct option is B All of the above
The time of flight only depends on vertical component of velocity and if A,B,C have same max height that means they have same vertical component of velocity i.e., same time of flight . (A) is correct.
If C covers maximum horizontal distance in same time as all three that means it has maximum horizontal velocity. (C) is correct.
If all of them have same vertical velocity and C have maximum horizontal velocity that implies C has highest total velocity. (B) is correct.
All the options are correct , (D) is correct . ( for single correct options only D)