Match the following list of animals with their level of organisation.
`{:("Division of Labour","Animal"),(A."Organ level",i."Pheretima"),(B."Cellular aggregate level",ii."Fasciola"),(C."Tissue level",iii."Spongilla"),(D."Organ system level",iv."Obelia"):}`
Choose the correct match showing division of labour with animal example.

Options

A. (i)-B, (ii)-C, (iii)-D and (iv)-A
B. (i)-B, (ii)-D, (iii)-C and (iv)-A
C. (i)-D, (ii)-A, (iii)-B and (iv)-C
D. (i)-A, (ii)-D, (iii)-C and (iv)-B

Explanation

To solve the question of matching animals with their level of organization, we need to analyze each animal and determine its corresponding level of organization. Here’s a step-by-step solution:

### Step 1: Identify the Levels of Organization
1. **Cellular Aggregate Level**: This level involves simple organisms that are made up of a collection of cells that perform similar functions but do not form true tissues.
2. **Tissue Level**: At this level, cells are organized into tissues that perform specific functions.
3. **Organ Level**: Here, different types of tissues come together to form organs that perform specific functions.
4. **Organ System Level**: This is a higher level of organization where different organs work together to perform complex functions.

### Step 2: Analyze Each Animal
1. **Pheretima (Earthworm)**: This organism has a complex structure with various organs working together, indicating it has an **Organ System Level** of organization.
2. **Fasciola (Liver Fluke)**: This organism has some organs but does not possess a complete organ system, so it is classified under the **Organ Level** of organization.
3. **Spongilla (Freshwater Sponge)**: As a member of the Porifera, Spongilla has a simple structure with a cellular aggregate level of organization.
4. **Obelia**: This organism has a more complex structure with tissues, indicating it has a **Tissue Level** of organization.

### Step 3: Match Each Animal with Its Level of Organization
- **A. Organ Level** → **ii. Fasciola**
- **B. Cellular Aggregate Level** → **iii. Spongilla**
- **C. Tissue Level** → **iv. Obelia**
- **D. Organ System Level** → **i. Pheretima**

### Final Matches
- **A (Organ Level)** → **ii (Fasciola)**
- **B (Cellular Aggregate Level)** → **iii (Spongilla)**
- **C (Tissue Level)** → **iv (Obelia)**
- **D (Organ System Level)** → **i (Pheretima)**

### Summary of the Correct Matches
- A - ii
- B - iii
- C - iv
- D - i