From statement I, we have, Prabhakar > Manoj, Prabhakar > Kamal, Akash > Prabhakar
From statement II we have, Manoj > Kamal, Prabhakar > Manoj, Akash > Manoj.
Combining the both the above two, we have : Akash > Prabhakar > Manoj > Kamal.
Thus, Akash is the heaviest. So, both the statements are required.
option D