(E)

35% is <= 2

25%>= 4

if there are 100 projects average of 50th and 51st in ascending order would be >=4 but not sure exactly how much.

I will go with C.

I and II insuff.

Taken together, 40% of the projects have exactly 3 members in the project. So

35%(with 2 or less), 40%(with 3), 25%(with 4 0r more).

what is OA

If 25% have 4 or more
and 35% have 2 or less
that implies that the remaining 40% have exactly 3 people.
If we have 100 projects altogether, the first 35 will have 2 or less people, the next 40 projects will have 3 people, and the last 25 projects will have 4 or more people. We know that the median is the average number of people between the 50th and 51st project. The 50th has 3 people, and the 51st has 3 people, so the median is 3. So the answer is C.

thanks, i guess C should be correct... as we have 3 groups===> 2-; x; 4+ therefore x will be between 2 & 4 which is 3, hence the median!