Loudness and Decibels
Loudness is a perceptual response to the intensity of sound, and it is commonly quantified using a logarithmic scale called decibels (dB). Here’s a detailed explanation of the relationship between loudness and decibels.

What are Decibels?
- Decibels are a unit of measurement that express the intensity of sound.
- They are based on a logarithmic scale, which means that an increase of 10 dB represents a tenfold increase in intensity.
- This scale allows for a more manageable representation of a wide range of sound levels, from the faintest whisper to a loud rock concert.

Understanding Loudness
- Loudness is subjective and can vary from person to person, even at the same sound intensity.
- The decibel scale helps provide a standardized way to communicate sound levels.
- For example, normal conversation typically measures around 60 dB, while sounds at 120 dB can cause discomfort or pain.

Real-World Applications
- The decibel scale is widely used in various fields, including music, engineering, and health.
- Occupational safety regulations often specify allowable noise levels in workplaces to protect hearing.
- Understanding decibels helps individuals make informed choices about sound exposure in daily life.
In conclusion, loudness is indeed expressed in decibels, making option 'A' the correct answer. The use of decibels simplifies the communication and understanding of loudness levels in our environment.