Read the featured given below and select the option for animals which correctly describes the features mentioned:
I. All are exclusively marine, triploblastic, coelomate organism with a water vascular system.
II. A small group of warm-like marine animals with the organ system levels of the organization.
III. The body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot, and visceral hump.
IV. Triploblastic, pesudocelomate animals in
which alimentary canal is complete with a well developed muscular pharynx.

Options

A. I-Asterias, II-Balanoglossus, III-Ascaris, IV-Ancylostoma
B. I-Ascaris, II-Ophiura, III-Pila, IV-Sepia
C. I-Ascaris, II-Saccoglossus, III-Sepia, IV-Ophiura
D. I-Asterias, II-Balanoglossus, III-Pila, IV-Ascaris

Answer

To solve the question, we will analyze each of the statements provided and identify the corresponding animal phyla and examples based on the features mentioned.

### Step-by-Step Solution:

1. **Statement I: All are exclusively marine, triploblastic, coelomate organisms with a water vascular system.**
- **Analysis:** This description fits the phylum **Echinodermata**, which includes marine animals like starfish (e.g., **Asteroidea**). They are triploblastic and coelomate, and they possess a water vascular system.
- **Example:** **Asteroidea (Starfish)**

2. **Statement II: A small group of worm-like marine animals with organ system levels of organization.**
- **Analysis:** This description aligns with the phylum **Hemichordata**, which consists of worm-like organisms that serve as a connecting link between chordates and non-chordates. They exhibit organ system organization.
- **Example:** **Balanoglossus**

3. **Statement III: The body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot, and visceral hump.**
- **Analysis:** This description is characteristic of the phylum **Mollusca**, which includes animals with a calcareous shell, a muscular foot, and a visceral hump. They are typically unsegmented.
- **Example:** **Pila (Apple snail)**

4. **Statement IV: Triploblastic, pseudocoelomate animals in which the alimentary canal is complete with a well-developed muscular pharynx.**
- **Analysis:** This description fits the phylum **Nematoda** (roundworms), which are triploblastic and pseudocoelomate. They have a complete digestive system and a muscular pharynx.
- **Example:** **Ascaris**

### Final Answers:
- **I:** Asteroidea (Starfish)
- **II:** Balanoglossus (Hemichordata)
- **III:** Pila (Mollusca)
- **IV:** Ascaris (Nematoda)