Who among P, Q, R, S and T is the lightest?
I. R is heavier than Q and T but lighter than S.
II. S is not the heaviest.

Options

A. the data in statement I alone are sufficient to answer the question, while the data in statement II alone are not sufficient to answer the question,
B. the data in statement II alone are sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question,
C. the data either in statement I alone or in statement II alone are sufficient to answer the question,
D. the data given in both statements I and II together are not sufficient to answer the question,

Explanation

To determine who among P, Q, R, S, and T is the lightest based on the given statements, we will analyze each statement step by step.

### Step 1: Analyze Statement I
**Statement I:** R is heavier than Q and T but lighter than S.

From this statement, we can establish the following relationships:
- R > Q (R is heavier than Q)
- R > T (R is heavier than T)
- S > R (S is heavier than R)

This means we can order these individuals based on their weights:
- S > R > Q
- S > R > T

However, we do not have any information about P or the relationship between Q and T. Therefore, we cannot determine who is the lightest among all five individuals based solely on this statement.

### Step 2: Analyze Statement II
**Statement II:** S is not the heaviest.

This statement tells us that S is not the heaviest, but it does not provide any specific information about the weights of P, Q, R, and T. Therefore, we cannot derive any conclusions about who is the lightest based on this statement alone.

### Step 3: Combine Both Statements
Now, let's combine both statements to see if we can derive any conclusions:
- From Statement I, we have: S > R > Q and S > R > T.
- From Statement II, we know that S is not the heaviest, which implies there is someone heavier than S, possibly P.

However, we still do not have any information about the relationship between Q and T. Since we cannot determine the weight of Q in relation to T, we still cannot conclude who is the lightest among all five individuals.

### Conclusion
Based on the analysis of both statements, we find that we cannot determine who is the lightest among P, Q, R, S, and T. Therefore, the answer is that the data given in both statements together are not sufficient to answer the question.

### Final Answer
The answer is: **Cannot be determined.**

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