What is true for corpus callosum?

Options

A. It connects the two thalami in brain of mammals and birds
B. It is a strip of nerves from midbrain to medulla oblongata in frog and mammals
C. It is a strip of nerves which connects two cerebral hemispheres of mammals only
D. It connects two cerebellar hemispheres of mammals only

Answer

**Step-by-Step Solution:**

1. **Understanding the Corpus Callosum**: The corpus callosum is a significant structure in the brain. It is a large C-shaped bundle of nerve fibers located beneath the cerebral cortex.

2. **Function of the Corpus Callosum**: Its primary function is to connect the left and right cerebral hemispheres, allowing for communication between the two sides of the brain.

3. **Evaluating the Options**:
- **Option 1**: "It connects the two thalami in the brain of mammals and birds." This is incorrect because the corpus callosum connects the cerebral hemispheres, not the thalami.
- **Option 2**: "It is a stripe of nerves from midbrain to medulla oblongata in mammals." This is also incorrect as the corpus callosum does not connect the midbrain to the medulla oblongata.
- **Option 3**: "It is a stripe of nerve which connects two cerebral hemispheres of mammals only." This is correct because the corpus callosum specifically connects the left and right hemispheres of the brain in mammals.
- **Option 4**: "It connects to cerebral hemispheres of the mammals only." This option is misleading because while it does connect the hemispheres, it does not specify that it is only mammals.

4. **Conclusion**: The correct answer is **Option 3**, as it accurately describes the function of the corpus callosum in mammals.

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