Correct Option: C. Wind Speed Detailed Explanation: An anemometer is a meteorological instrument specifically designed to measure wind speed. Understanding how it works and its applications can help clarify why option C is the correct answer.

1. Function of an Anemometer:
2. An anemometer typically consists of several cups or blades that rotate when wind passes over them. The speed at which these cups or blades rotate is directly proportional to the wind speed. The faster the wind blows, the faster the cups spin. This rotation can be translated into a measurement of wind speed, usually expressed in units such as meters per second (m/s) or miles per hour (mph).
3. Types of Anemometers:
4. There are various types of anemometers, including cup anemometers, vane anemometers, and hot-wire anemometers. Each type operates on slightly different principles but ultimately serves the same purpose: measuring wind speed.
5. Applications:
6. Anemometers are widely used in meteorology, aviation, marine navigation, and even in the renewable energy sector to assess wind conditions for wind turbine placement.

Why Other Options Are Incorrect:

• A. Relative Humidity:
• Relative humidity is a measure of the amount of moisture in the air compared to the maximum amount of moisture the air can hold at a given temperature. Instruments used to measure relative humidity include hygrometers and psychrometers, not anemometers. Therefore, this option is incorrect.
• B. Altitude:
• Altitude refers to the height of an object or point in relation to sea level or ground level. Instruments that measure altitude include altimeters and barometers. An anemometer does not measure altitude, making this option incorrect.
• D. Turbidity:
• Turbidity is a measure of the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye. Instruments that measure turbidity are called turbidimeters. An anemometer does not measure turbidity, so this option is also incorrect.

Summary of Key Points:

• An anemometer measures wind speed, making option C the correct answer.
• It operates by using rotating cups or blades that respond to wind flow.
• Other options (A, B, D) refer to different measurements (humidity, altitude, turbidity) and are not functions of an anemometer.
• Understanding the specific functions of various instruments is crucial for accurate identification and application in scientific contexts.