Number of middle ear bones in mammals is

Options

A. one
B. two
C. three
D. zero

Answer

To answer the question regarding the number of middle ear bones in mammals, we can follow these steps:

### Step 1: Understand the Anatomy of Mammals
Mammals are characterized by having three middle ear bones, which are known as the ossicles. These bones are the malleus (hammer), incus (anvil), and stapes (stirrup).

### Step 2: Identify the Function of Middle Ear Bones
The primary function of these middle ear bones is to transmit sound vibrations from the outer ear to the inner ear. This is crucial for the hearing process in mammals.

### Step 3: Confirm the Number of Middle Ear Bones
In mammals, regardless of the specific group (e.g., monotremes, marsupials, placental mammals), the number of middle ear bones remains consistent at three.

### Step 4: Conclusion
Thus, the number of middle ear bones in mammals is three.

### Final Answer
The number of middle ear bones in mammals is **three**.

---