The smallest organisms which cause diseases among plants are

Options

A. Mycoplasma
B. Fungi
C. Bacteria
D. Viruses

Answer

To answer the question "The smallest organisms which cause diseases among plants are," we can follow these steps:

### Step 1: Identify the Organisms
We need to consider the options provided: Mycoplasma, Fungi, Bacteria, and Viruses.

### Step 2: Analyze Each Option
- **Fungi**: These are relatively larger organisms and are not the smallest.
- **Bacteria**: While they are small, they are larger than Mycoplasma and viruses.
- **Viruses**: These are known to be very small and can cause diseases in plants.
- **Mycoplasma**: These are even smaller than bacteria and viruses and are known to cause diseases in plants.

### Step 3: Determine the Smallest
Among these, Mycoplasma is recognized as the smallest organism that can cause diseases in plants. They are prokaryotic and can survive without oxygen.

### Step 4: Conclusion
Based on the analysis, the smallest organisms which cause diseases among plants are **Mycoplasma**.

### Final Answer
**A. Mycoplasma**

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