Final answer:
Carbohydrates are a crucial macronutrient that provides energy, forms part of the plasma membrane, and facilitates cell recognition. They are found in grains, fruits, and vegetables and serve as an essential part of our diet. Option b is correct.
Step-by-step explanation:
The question deals with the role of carbohydrates in the body and their importance as a macronutrient. Carbohydrates serve as the main source of energy for the body, are an essential component of the plasma membrane, and play a critical role in cell recognition.
They can be found in various forms, such as glucose, starch, and cellulose, with each form having specific functions and properties. Grains, fruits, and vegetables are natural sources of carbohydrates that provide energy, particularly through glucose.
It is important to consume carbohydrates because they are not only an important source of energy but also have other critical functions in human, animal, and plant biology.