Identify the incorrect match from those given below

Options

A. Jelly fish Aurelia aurita Scyphozoa
B. Paddle worm Chaetopterus Polychaeta
C. Cray fish Oniscus Crustacea
D. Acom worm Balanoglossus Enteropneusta

Explanation

To identify the incorrect match from the options given, we will analyze each option one by one.

### Step 1: Analyze the first option
- **Option:** Jellyfish
- **Scientific Name:** Aurelia aurita
- **Class:** Scyphozoa

**Analysis:**
The scientific name Aurelia aurita is indeed the correct name for jellyfish, and it belongs to the class Scyphozoa. Therefore, this match is correct.

### Step 2: Analyze the second option
- **Option:** Paddle Worm
- **Scientific Name:** Chaetopterus
- **Class:** Polychaeta

**Analysis:**
The scientific name Chaetopterus is accurate for paddle worms, and they belong to the class Polychaeta. Thus, this match is also correct.

### Step 3: Analyze the third option
- **Option:** Crayfish
- **Scientific Name:** Oniscus
- **Class:** Crustacea

**Analysis:**
Here, the scientific name given is Oniscus, which is incorrect for crayfish. The correct scientific name for crayfish is Astacus. However, Crustacea is the correct class for crayfish. Therefore, this match is incorrect due to the wrong scientific name.

### Step 4: Analyze the fourth option
- **Option:** Acorn Worm
- **Scientific Name:** Balanoglossus
- **Class:** Enteropneusta

**Analysis:**
The scientific name Balanoglossus is correct for acorn worms, and they belong to the class Enteropneusta. Therefore, this match is correct.

### Conclusion
The incorrect match is the third option, where the scientific name for crayfish is incorrectly stated as Oniscus instead of Astacus.

### Final Answer
The incorrect match is the third option: Crayfish - Oniscus (should be Astacus).

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