Which of the following is a single U shaped bone present at the base of a buccal cavity and is intended in the skull ?

Options

A. Zygomatic
B. Hyoid
C. Mandible
D. Ethmoid

Answer

To solve the question, "Which of the following is a single U-shaped bone present at the base of a buccal cavity and is intended in the skull?" we can follow these steps:

### Step 1: Understand the Question
We need to identify a specific bone that is described as U-shaped, located at the base of the buccal cavity, and is part of the skull.

### Step 2: Analyze the Options
Let's look at the options provided:
- a. Zygomatic
- b. Hyoid
- c. Mandible
- d. Ethmoid

### Step 3: Evaluate Each Option
1. **Zygomatic Bone**: This bone is commonly known as the cheekbone and is not U-shaped. It is located on the sides of the face, not at the base of the buccal cavity.

2. **Hyoid Bone**: This bone is indeed U-shaped and is located in the neck region, just below the mandible. It serves as an attachment point for the tongue and muscles of the oral cavity. It is not directly articulated with other bones, which aligns with the description in the question.

3. **Mandible**: This is the lower jawbone and is not U-shaped; it is more of a horseshoe shape and is not located at the base of the buccal cavity in the same context as the hyoid.

4. **Ethmoid Bone**: This bone is located in the skull, between the nasal cavity and the orbits, and does not fit the description of being U-shaped or located at the base of the buccal cavity.

### Step 4: Conclusion
Based on the analysis, the only option that fits all the criteria of being a single U-shaped bone at the base of the buccal cavity is the **Hyoid Bone**.

### Final Answer
The correct answer is **b. Hyoid**.

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