In Cockroach, the common duct of salivary reservoir opens at the base of………

Options

A. Pharynx
B. Maxilla
C. Mandible
D. Hypopharynx

Answer

To solve the question regarding where the common duct of the salivary reservoir opens in a cockroach, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Anatomy of Cockroach**:
- Cockroaches have a complex mouth structure that includes various parts such as the mandible, maxilla, hypopharynx, and pharynx.

2. **Identify the Salivary Glands**:
- Cockroaches possess a pair of salivary glands that produce saliva, which contains enzymes like amylase that help in digestion.

3. **Locate the Common Duct**:
- The common duct of the salivary reservoir is the passage through which saliva flows from the salivary glands into the mouth.

4. **Determine the Opening Location**:
- The question asks where this common duct opens. The salivary duct opens at the base of the buccal cavity.

5. **Identify the Correct Answer**:
- The base of the buccal cavity is represented by the hypopharynx in cockroaches. Therefore, the common duct of the salivary reservoir opens at the base of the hypopharynx.

6. **Eliminate Incorrect Options**:
- The other options (pharynx, maxilla, mandible) do not accurately describe the location where the salivary duct opens. The pharynx is a broader term for the throat area, while maxilla and mandible are specific mouthparts, not the opening for the salivary duct.

### Final Answer:
The common duct of the salivary reservoir in a cockroach opens at the base of the **hypopharynx**.

---