In a frog, the connection between brain and spinal cord is severed. The leg of such a frog is picked by a sharp needle. Then it is most likely that the animal will

Options

A. Not show any reaction
B. Move the leg that is picked
C. Move the leg and feel the pain
D. Do not move the leg but feel the pain

Answer

### Step-by-Step Solution:

1. **Understanding the Scenario**: The question states that in a frog, the connection between the brain and spinal cord is severed. This means that the brain cannot communicate with the spinal cord.

2. **Identifying Reflex Actions**: Reflex actions are automatic responses to stimuli that do not require the involvement of the brain. They are controlled by the spinal cord. In this case, the reflex arc is intact because the spinal cord is still functional.

3. **Stimulus Application**: When the leg of the frog is poked with a sharp needle, a stimulus is applied to the leg. The sensory receptors in the leg will detect this stimulus.

4. **Reflex Arc Activation**: Since the connection to the brain is severed, the sensory information from the leg will travel to the spinal cord, which will process this information and initiate a reflex response.

5. **Response to the Stimulus**: The spinal cord will send a signal back to the muscles of the leg to contract, resulting in the movement of the leg away from the sharp object. This is a reflex action and does not require any input from the brain.

6. **Conclusion**: Therefore, the most likely response of the frog when its leg is poked with a sharp needle is that it will move the leg that is picked.

### Final Answer:
The animal will **move the leg that is picked**.

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