This is a data sufficiency question. We need to determine if the statements, alone or together, are sufficient to answer the question "Who is the heaviest?".
Analyze Statement I: "Rahul is heavier than Deepak and Vinod, but lighter than Manoj." From this, we can establish the following orderings: Rahul > Deepak Rahul > Vinod Manoj > Rahul Combining these, we get the order: Manoj > Rahul > (Deepak, Vinod). This statement clearly establishes that Manoj is the heaviest of the four. Therefore, Statement I alone is sufficient to answer the question.
Analyze Statement II: "Deepak is lighter than Rahul and Manoj, but heavier than Vinod." From this, we get: Rahul > Deepak Manoj > Deepak Deepak > Vinod Combining these, we get: (Rahul, Manoj) > Deepak > Vinod. This statement tells us that Vinod is the lightest and Deepak is the second lightest, but it does not tell us who is heavier between Rahul and Manoj. So, we cannot determine who is the heaviest from Statement II alone.
Conclusion: Since Statement I alone is sufficient and Statement II alone is not sufficient, the correct option is (C).
How many triangles are there in the figure given below? 