Study the following statements and choose the correct answer :
I. Cross -pollinating flowers have exotrose anthers .
II. Samara is a type of fleshy fruit.
III. Marginal placentation has a monocarpellary , unilocular ovary .
IV. Opposite phyllotaxy is seen in guava.

Options

A. II and IV are correct but I and II are wrong
B. II and I are correct but III and IV are wrong
C. I, II and IV are correct but III is wrong
D. III and IV are correct but I and II is wrong

Answer

To solve the question, we need to evaluate each of the statements provided and determine which ones are correct.

### Step 1: Evaluate Statement I
**Statement I:** Cross-pollinating flowers have exotrose anthers.
- **Analysis:** This statement is incorrect. Cross-pollinating flowers typically have **introrse** anthers, which are positioned to release pollen inward toward the stigma. **Exotrose** anthers are found in self-pollinating flowers.

### Step 2: Evaluate Statement II
**Statement II:** Samara is a type of fleshy fruit.
- **Analysis:** This statement is also incorrect. A **samara** is a type of dry fruit that is winged and is not fleshy. An example of a fleshy fruit would be a mango or a peach.

### Step 3: Evaluate Statement III
**Statement III:** Marginal placentation has a monocarpellary, unilocular ovary.
- **Analysis:** This statement is correct. **Marginal placentation** occurs in a single-carpel ovary (monocarpellary) and is unilocular, meaning it has one chamber. This type of placentation is commonly seen in the Fabaceae family.

### Step 4: Evaluate Statement IV
**Statement IV:** Opposite phyllotaxy is seen in guava.
- **Analysis:** This statement is correct. Guava (Psidium guajava) exhibits **opposite phyllotaxy**, where two leaves arise at each node opposite to each other.

### Conclusion
- **Correct Statements:** III and IV are correct.
- **Incorrect Statements:** I and II are incorrect.

### Final Answer
The correct answer is that statements III and IV are correct.