Which of the following is not monoecious plant?

Options

A. Cycas
B. Pinus
C. Wheat
D. Mustard

Answer

To determine which of the following plants is not monoecious, we need to understand the definitions and characteristics of monoecious and dioecious plants.

### Step-by-Step Solution:

1. **Understand the Terms:**
- **Monoecious:** A plant species that has both male and female reproductive organs on the same individual. This means that a single plant can produce both pollen (male gametes) and ovules (female gametes).
- **Dioecious:** A plant species where male and female reproductive organs are on separate individuals. This means that one plant will produce only male gametes and another plant will produce only female gametes.

2. **Analyze the Options:**
- **Option 1: Cyclus (Cycads)**
- Cyclus is a gymnosperm that has both male and female cones on the same plant. Therefore, it is monoecious.
- **Option 2: Ginkgo biloba**
- Ginkgo biloba is a gymnosperm where male and female cones are found on different plants. Thus, it is dioecious.
- **Option 3: Mustard**
- Mustard is an angiosperm that has both male and female flowers on the same plant, making it monoecious.
- **Option 4: Wheat**
- Wheat is also an angiosperm that has both male and female reproductive structures on the same plant, hence it is monoecious.

3. **Identify the Correct Answer:**
- From the analysis, we see that **Ginkgo biloba** (Option 2) is the only plant listed that is dioecious, meaning it is not monoecious.

### Final Answer:
**Ginkgo biloba (Option 2) is not a monoecious plant.**

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