All the following statemnts are correct about the reproductive system of earthwrom, but one is wrong. Which one is wrong?

Options

A. There are two pairs of testes one pair in the 10th and one pair of 11th segment
B. One pair of ovaries attached at the inter-segmental septum of the 12th and 13th segment
C. Two pairs of accessory glands one pair each in 18th and 19th segments
D. Four pairs of spermatheca are located in 6th-9th segments, one pair in each segments.

Explanation

To determine which statement about the reproductive system of earthworms is incorrect, we will analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Statement Analysis**:
- **Statement 1**: "There are two pairs of testis, one pair in the 10th and one pair in the 11th segment."
- This statement is **correct**. Male earthworms have a pair of testes located in the 10th and 11th segments.

2. **Statement 2**: "One pair of ovaries attached at the intersegmental septum of the 12th and 13th segment."
- This statement is **correct**. Female earthworms have a pair of ovaries located at the intersegmental septum between the 12th and 13th segments.

3. **Statement 3**: "Two pairs of accessory glands, one pair each in the 18th and 19th segment."
- This statement is **incorrect**. The accessory glands are actually present in the 17th and 19th segments, not the 18th and 19th segments. Therefore, this is the wrong statement.

4. **Statement 4**: "Four pairs of spermatheca are located in the six to nine segments, one in each segment."
- This statement is **correct**. Earthworms have four pairs of spermathecae located in segments 6 to 9, with one pair in each segment.

### Conclusion:
The incorrect statement regarding the reproductive system of earthworms is the third statement about the accessory glands.

### Final Answer:
The wrong statement is: "Two pairs of accessory glands, one pair each in the 18th and 19th segment."

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