Which of the following set of organisms shows dioecious conditions ?

Options

A. Ancylostoma, Aedes, Limulus
B. Ancylostoma, Periplaneta, Pheretima
C. Aedes, Limulus, Hirudinaria
D. Fasciola, Ascaris, Ophiura

Answer

To determine which set of organisms shows dioecious conditions, we need to understand the definitions of dioecious and monoecious organisms.

### Step-by-Step Solution:

1. **Define Dioecious and Monoecious:**
- **Dioecious:** Organisms that have male and female reproductive organs on separate individuals. This means that one organism will produce only male gametes and another will produce only female gametes.
- **Monoecious:** Organisms that have both male and female reproductive organs in the same individual. This means that a single organism can produce both types of gametes.

2. **Analyze Each Option:**
- **Option A:** Inclined stoma, Aedes, and Limulus.
- **Inclined stoma** (Ankylostoma) is dioecious.
- **Aedes** (a genus of mosquitoes) is dioecious.
- **Limulus** (horseshoe crab) is dioecious.
- **Conclusion:** All three are dioecious.

- **Option B:** Inclined stoma, Periplaneta, Ferritima.
- **Inclined stoma** is dioecious.
- **Periplaneta** (American cockroach) is monoecious.
- **Ferritima** (a genus of earthworms) is also monoecious.
- **Conclusion:** Not all are dioecious.

- **Option C:** Aedes, Limulus, Herudinaria.
- **Aedes** is dioecious.
- **Limulus** is dioecious.
- **Herudinaria** (a genus of leeches) is monoecious.
- **Conclusion:** Not all are dioecious.

- **Option D:** Fasciola, Ascaris, and Ophiora.
- **Fasciola** (liver fluke) is monoecious.
- **Ascaris** (a genus of roundworms) is dioecious.
- **Ophiora** (brittle stars) is dioecious.
- **Conclusion:** Not all are dioecious.

3. **Final Conclusion:**
- The only option where all organisms are dioecious is **Option A: Inclined stoma, Aedes, and Limulus**.

### Answer:
The correct answer is **Option A: Inclined stoma, Aedes, and Limulus.**

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