In florescence with unisexual sessile flower is

Options

A. spike
B. spikelet
C. catkin
D. spadix

Answer

To solve the question regarding which type of inflorescence has unisexual sessile flowers, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for an inflorescence type that has unisexual (either male or female) sessile (attached directly to the stem without a stalk) flowers.

2. **Analyzing Option 1: Spike**:
- A spike is a type of racemose inflorescence where flowers are sessile.
- However, spikes typically contain bisexual flowers (both male and female).
- **Conclusion**: This option does not meet the criteria of unisexual flowers.

3. **Analyzing Option 2: Spikelet**:
- A spikelet is a small and specialized spike that contains one or more florets.
- It is also a type of racemose inflorescence.
- Spikelets can contain both unisexual and bisexual flowers, but they are usually associated with grasses.
- **Conclusion**: This option is not correct as it does not specifically refer to unisexual sessile flowers.

4. **Analyzing Option 3: Catkin**:
- A catkin is a type of racemose inflorescence that is typically pendulous (hanging).
- Catkins can contain unisexual flowers and are often sessile.
- Examples include plants like willows and oaks, which produce unisexual flowers in catkins.
- **Conclusion**: This option meets the criteria of having unisexual sessile flowers, making it the correct answer.

5. **Analyzing Option 4: Spadix**:
- A spadix is a fleshy spike that contains both male and female flowers.
- It is surrounded by a large bract called a spathe.
- Since it contains both types of flowers, it is classified as bisexual.
- **Conclusion**: This option does not meet the criteria of unisexual flowers.

### Final Answer:
The correct answer is **Option 3: Catkin**, as it is an inflorescence with unisexual sessile flowers.