A person can catch cold from

Options

A. a healthy person
B. a handshake
C. a sudden drop in temperature
D. none of these.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Disease**: The question is about how a person can catch a cold, specifically the common cold, which is primarily caused by viruses, particularly Rhinoviruses.

2. **Identifying Symptoms**: Common cold symptoms include a sore throat, cough, headache, and tiredness. These symptoms typically last for 3 to 7 days.

3. **Transmission of the Virus**: The common cold spreads through droplets that are expelled when an infected person coughs or sneezes. These droplets can be inhaled by a healthy person or can land on surfaces.

4. **Evaluating the Options**:
- **From a Healthy Person**: This option is incorrect because a healthy person does not have the virus to transmit.
- **A Handshake**: This option is correct. If an infected person coughs or sneezes, droplets can land on their hands and be transferred to another person through a handshake.
- **A Sudden Drop in Temperature**: This option is incorrect. While cold weather can influence immunity, it does not directly cause a cold.
- **None of These**: This option is incorrect since a handshake can indeed lead to catching a cold.

5. **Conclusion**: The correct answer is that a person can catch a cold from a handshake, as it allows for the transfer of infectious droplets from an infected person.

**Final Answer**: A person can catch cold from a handshake.

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