Refer to the given passage and answer the following questions. P, Q and R are acoelomate organisms whereas S and T are true coelomates. P possesses cellular level of body organisation whereas others possess tissue and organ level of body organisation. Q possesses special stinging cells called cnidoblasts. R is the first triploblastic animal and has flame cells as excretory organs. The body of S is metamerically segmented whereas T bears jointed appendages and chitinous exoskeleton.
Which of the following is incorrect regarding organisms P, Q, R, S and T?

Options

A. P possesses endoskeleton of calcareous spicules whereas Q is always aquatic.
B. R could be a parasite which attaches to the body of host through hooks and suckers whereas S possesses metanephridia for excretion.
C. T sheds off its chitinous exoskeleton periodically during its growth which is referred to as moulting.
D. None of these

Answer

To solve the question regarding the organisms P, Q, R, S, and T, we need to analyze the information provided in the passage step by step.

### Step-by-Step Solution:

1. **Identify the Organisms and Their Characteristics:**
- **P**: Acoelomate, cellular level of body organization (likely a member of Porifera).
- **Q**: Acoelomate, possesses cnidoblasts (stinging cells), indicating it belongs to the phylum Cnidaria.
- **R**: Acoelomate, first triploblastic animal, has flame cells as excretory organs (indicating it belongs to the phylum Platyhelminthes).
- **S**: True coelomate, metamerically segmented (indicating it belongs to the phylum Annelida).
- **T**: True coelomate, bears jointed appendages and a chitinous exoskeleton (indicating it belongs to the phylum Arthropoda).

2. **Analyze Each Statement:**
- **Statement about P**: P is a cellular level organism (correct).
- **Statement about Q**: Q possesses cnidoblasts (correct).
- **Statement about R**: R is the first triploblastic animal with flame cells (correct).
- **Statement about S**: S is metamerically segmented (correct).
- **Statement about T**: T has jointed appendages and a chitinous exoskeleton (correct).

3. **Consider Possible Incorrect Statements:**
- The question asks for an incorrect statement regarding P, Q, R, S, and T.
- Based on the characteristics outlined, all statements provided in the passage about the organisms appear to be correct.

4. **Conclusion:**
- Since all the statements about P, Q, R, S, and T are accurate, the answer to the question is that there is no incorrect statement among them.

### Final Answer:
None of the statements regarding organisms P, Q, R, S, and T are incorrect.

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