As: Acetabularia is the largest sized single celled green algae.
R PPLO is the smallest sized prokaryote.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

To solve the question regarding the assertion and reason provided, we will follow these steps:

### Step 1: Understand the Assertion
The assertion states that "Acetabularia is the largest sized single-celled green algae."
- **Analysis**: Acetabularia is indeed known to be one of the largest single-celled algae, often reaching lengths of up to 10 centimeters. Thus, the assertion is **correct**.

### Step 2: Understand the Reason
The reason states that "PPLO is the smallest sized prokaryote."
- **Analysis**: PPLO stands for Pleuropneumonia-like organisms, which includes Mycoplasma. Mycoplasma is recognized as one of the smallest known prokaryotic organisms. Therefore, the reason is also **correct**.

### Step 3: Determine the Relationship Between Assertion and Reason
Next, we need to evaluate whether the reason provided is a correct explanation of the assertion.
- **Analysis**: While both statements are correct, they are not related to each other. The size of Acetabularia does not explain or relate to the size of PPLO or Mycoplasma. Thus, the reason is **not a correct explanation** of the assertion.

### Step 4: Choose the Correct Option
Now, we will look at the options provided:
- **Option A**: Both assertion and reason are correct, and the reason is the correct explanation of the assertion. (Incorrect)
- **Option B**: Both assertion and reason are correct, but the reason is not the correct explanation of the assertion. (Correct)
- **Option C**: Assertion is correct, but reason is wrong. (Incorrect)
- **Option D**: Both assertion and reason are wrong. (Incorrect)

Based on our analysis, the correct option is **Option B**.

### Final Answer:
**Option B**: Both assertion and reason are correct, but the reason is not the correct explanation of the assertion.

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