Select the correct statement from the ones given below with respect to Periplaneta americana.

Options

A. There are 16 very long Malpighian tubules present at the junctions of midgut and hindgut
B. Grinding of food is carried out only by the mouth parts
C. Nervous system located dorsally, consists of segmentally arranged ganglia joined by a pair of longitudinal connective
D. Males bear a pair of short thread like anal styles

Answer

To solve the question regarding the correct statement about Periplaneta americana (the American cockroach), we will analyze each of the provided statements step by step.

### Step-by-Step Solution:

1. **Examine the First Statement:**
- **Statement:** "There are 16 very long Malpighian tubules present at the junctions of Midgut and Hindgut."
- **Analysis:** This statement is incorrect. In Periplaneta americana, there are actually 150 Malpighian tubules, which are long, thread-like structures involved in excretion. They are located at the junction of the midgut and hindgut.

2. **Examine the Second Statement:**
- **Statement:** "Grinding of food is carried out only by the mouth parts."
- **Analysis:** This statement is also incorrect. The grinding of food in cockroaches is performed not only by the mouth parts but also by the mandibles, labrum, labium, and maxillae, which all assist in the mechanical breakdown of food.

3. **Examine the Third Statement:**
- **Statement:** "Nervous system located dorsally consisting of segmentally arranged ganglia joined by a pair of longitudinal connective."
- **Analysis:** This statement is incorrect as well. The nervous system of the cockroach is indeed segmentally arranged, but it is located ventrally, not dorsally.

4. **Examine the Fourth Statement:**
- **Statement:** "Male bears a pair of short, thread-like anal styles."
- **Analysis:** This statement is correct. Male cockroaches do have a pair of short, thread-like anal styles, while females do not possess these structures.

### Conclusion:
The correct statement regarding Periplaneta americana is the fourth one: "Male bears a pair of short, thread-like anal styles." Therefore, the answer is option B.

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