Some animals are given in the list below
Asterias, Pila, Echinus, Antedon, Pinctada, Cucumaria, Octopus, Loligo, Ophiura, Dentalium.
How many animals among these are related to the second largest phylum of animals?

Options

A. Two
B. Three
C. Four
D. Five

Answer

To determine how many animals from the given list belong to the second largest phylum of animals, we will follow these steps:

### Step-by-Step Solution:

1. **Identify the Second Largest Phylum**:
The second largest phylum of animals is **Mollusca**.

2. **List the Given Animals**:
The animals provided in the question are:
- Asterias
- Pila
- Echinus
- Antedon
- Pinctada
- Cucumaria
- Octopus
- Loligo
- Ophiura
- Dentalium

3. **Classify Each Animal by Phylum**:
- **Asterias**: Belongs to Phylum **Echinodermata** (Starfish)
- **Pila**: Belongs to Phylum **Mollusca** (Apple snail)
- **Echinus**: Belongs to Phylum **Echinodermata** (Sea urchin)
- **Antedon**: Belongs to Phylum **Echinodermata** (Sea lily)
- **Pinctada**: Belongs to Phylum **Mollusca** (Pearl oyster)
- **Cucumaria**: Belongs to Phylum **Echinodermata** (Sea cucumber)
- **Octopus**: Belongs to Phylum **Mollusca** (Devilfish)
- **Loligo**: Belongs to Phylum **Mollusca** (Squid)
- **Ophiura**: Belongs to Phylum **Echinodermata** (Brittle star)
- **Dentalium**: Belongs to Phylum **Mollusca** (Tusk shell)

4. **Count the Members of Mollusca**:
From the classification:
- Pila (1)
- Pinctada (2)
- Octopus (3)
- Loligo (4)
- Dentalium (5)

Thus, there are **5 animals** from the list that belong to the phylum Mollusca.

5. **Final Answer**:
The number of animals related to the second largest phylum (Mollusca) is **5**.