Which is correct ?

Options

A. Echinodermata-Starfish, Petromyzon, Solen
B. Mollusca-Pila,Dentalium, Octopus
C. Porifera-Spongilla,Teredo, Leucosolenia
D. Arthropoda-Pinworm, Ascaris, Cockroach.

Answer

To solve the question regarding which statement is correct, we will analyze each option provided:

### Step-by-Step Solution:

1. **Option 1: Echinodermata includes starfish, petromyson, and solan.**
- Echinodermata is a phylum that includes marine animals such as starfish (Asteroidea). However, Petromyson (also known as lampreys) belongs to the phylum Chordata, and Solan (which likely refers to a type of mollusk) belongs to Mollusca. Therefore, this option is incorrect.

2. **Option 2: Mollusca includes Pila, Dentallium, and Octopus.**
- Mollusca is a diverse phylum that includes various classes of animals. Pila (apple snail), Dentallium (elephant tusk shell), and Octopus (a cephalopod) all belong to the Mollusca phylum. Thus, this option is correct.

3. **Option 3: Porifera includes Spongyla, Pteridome, and Leucoselenia.**
- Porifera, or sponges, do include Spongyla and Leucoselenia. However, Pteridome (which is likely a misspelling or misclassification) does not belong to Porifera; it is related to Mollusca. Therefore, this option is incorrect.

4. **Option 4: Orthopoda includes pinworm, ascaris, and cockroach.**
- The phylum Arthropoda (not Orthopoda) includes insects like cockroaches, which are characterized by jointed legs and segmented bodies. Pinworm and Ascaris are nematodes (roundworms) and belong to the phylum Nematoda. Therefore, this option is incorrect.

### Conclusion:
The only correct statement is **Option 2: Mollusca includes Pila, Dentallium, and Octopus.**

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