Which of the following is NOT a common characteristic of carotenoids?

The choice indicating that carotenoids are antibiotics is not accurate because carotenoids do not function as antibiotics. Instead, carotenoids are primarily known for their role in adding color to fruits and vegetables, providing nutritional benefits such as serving as antioxidants, and being insoluble in water.

Carotenoids are pigments responsible for the vibrant colors seen in many plants, especially in fruits and vegetables like carrots, tomatoes, and spinach. They contribute not only to the aesthetic appeal of these foods but are also important for human health, particularly due to their antioxidant properties, which help combat oxidative stress in the body. Additionally, their insolubility in water is a characteristic that influences how they are absorbed and utilized in the body, typically requiring fats for optimal absorption.

Understanding these characteristics helps underline the roles carotenoids play in nutrition and biochemistry, distinguishing them from substances like antibiotics, which are specifically designed to target bacterial infections.