What is correct about Taenia ?

Options

A. Male organs occur in posterior proglottids
B. Male organs occur in anterior proglottids
C. Female organs occur in anterior proglottids
D. Mature proglottids contain both male and female organs

Explanation

To determine what is correct about Taenia, we need to analyze the structure and reproductive organs of its proglottids. Here’s a step-by-step solution:

### Step 1: Understand Proglottids
- Taenia, a type of tapeworm, has a segmented body made up of units called proglottids. There are three types of proglottids: immature, mature, and gravid.

### Step 2: Identify the Characteristics of Each Proglottid Type
- **Immature Proglottids**: These are located at the anterior end of the tapeworm and do not contain any reproductive organs.
- **Mature Proglottids**: These are found in the middle section of the tapeworm. Initially, they contain only male reproductive organs, but as they mature, they develop female reproductive organs as well.
- **Gravid Proglottids**: These are located at the posterior end and are filled with a branched uterus packed with fertilized eggs. They do not contain any reproductive organs.

### Step 3: Evaluate the Given Statements
1. **Male organs occur in posterior proglottids**: This is incorrect because posterior (gravid) proglottids do not have reproductive organs.
2. **Male organs occur in anterior proglottids**: This is also incorrect since anterior (immature) proglottids lack reproductive organs.
3. **Female organs occur in anterior proglottids**: This is incorrect as well, as anterior proglottids do not have reproductive organs.
4. **Mature proglottids contain both male and female organs**: This is correct. Mature proglottids are hermaphroditic, meaning they possess both male and female reproductive organs.

### Conclusion
The correct statement about Taenia is that mature proglottids contain both male and female organs.