Reflex actions are controlled by brain.

Explanation

### Step-by-Step Solution:

1. **Understanding Reflex Actions**: Reflex actions are automatic and involuntary responses to stimuli. They occur quickly and do not require conscious thought, allowing for rapid responses to potentially harmful situations.

2. **Role of the Nervous System**: The nervous system is responsible for controlling reflex actions. It consists of the brain, spinal cord, and peripheral nerves.

3. **Spinal Cord's Function**: Reflex actions are primarily controlled by the spinal cord, not the brain. The spinal cord processes the information from sensory neurons and sends a response through motor neurons to the muscles.

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