In which one of the following the genus name, its two characters and its phylum are not correctly mathced. Whereas the remaining three are correct.

Answer

To solve the question, we need to analyze the given options and identify which one contains an incorrect match between the genus name, its two characteristics, and its phylum. Here’s a step-by-step breakdown of the solution:

### Step 1: Analyze Option A (Genus: Pila)
- **Genus Name**: Pila
- **Phylum**: Mollusca
- **Characteristics**:
1. Body is unsegmented.
2. Mouth with radula (rasping organ).

**Evaluation**:
- Pila does belong to the phylum Mollusca, and it is known for having an unsegmented body and a radula. However, if any characteristic states that the body is segmented, it would be incorrect.

### Step 2: Analyze Option B (Genus: Ascaris)
- **Genus Name**: Ascaris
- **Phylum**: Echinodermata
- **Characteristics**:
1. Spiny skinned body.
2. Water vascular system.

**Evaluation**:
- Ascaris actually belongs to the phylum Nematoda, not Echinodermata. This is a mismatch.

### Step 3: Analyze Option C (Genus: Sycon)
- **Genus Name**: Sycon
- **Phylum**: Porifera
- **Characteristics**:
1. Pore-bearing organism.
2. Canal system present.

**Evaluation**:
- Sycon is correctly matched with the phylum Porifera. Both characteristics are accurate.

### Step 4: Analyze Option D (Genus: Periplaneta)
- **Genus Name**: Periplaneta
- **Phylum**: Arthropoda
- **Characteristics**:
1. Jointed appendages.
2. Exoskeleton made of chitin.

**Evaluation**:
- Periplaneta (cockroach) is correctly matched with the phylum Arthropoda. Both characteristics are accurate.

### Conclusion
After analyzing all options, we find that:
- **Option A** is correct in terms of Pila being unsegmented and having a radula, but if it states segmented, that is incorrect.
- **Option B** is incorrect as Ascaris belongs to Nematoda, not Echinodermata.
- **Options C and D** are correctly matched.

Thus, the answer is **Option B** as it contains the incorrect match.

### Final Answer
**The genus name, its two characters, and its phylum that are not correctly matched is: Option B (Ascaris, Echinodermata).**

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