Reflex action exhibited by

Options

A. Sympathetic system
B. Sensory nerves
C. Automatic response
D. Motor nerves

Answer

### Step-by-Step Solution:

1. **Understanding Reflex Action**: Reflex action is an involuntary and automatic response to a stimulus. It occurs without the involvement of conscious thought, meaning it happens quickly and without deliberation.

2. **Components of Reflex Action**: Reflex actions involve five main components:
- **Receptor**: A sensory organ that detects the stimulus.
- **Afferent Neurons**: Nerves that carry the sensory information from the receptor to the central nervous system (CNS).
- **Central Nervous System (CNS)**: In the case of reflex actions, this is primarily the spinal cord, which processes the information.
- **Efferent Neurons**: Nerves that carry the response signal from the CNS to the effector organ.
- **Effector**: The organ (usually a muscle or gland) that carries out the response.

3. **Process of Reflex Action**:
- A stimulus is detected by the receptor.
- The receptor sends a signal via afferent neurons to the spinal cord.
- The spinal cord processes this information and sends a response signal through efferent neurons.
- The effector (muscle or gland) responds accordingly (e.g., muscle contraction or gland secretion).

4. **Conclusion**: Reflex actions are exhibited by various organisms, including humans, and are crucial for survival as they allow for quick responses to potentially harmful stimuli.