Here's why:

* Structure: Carbohydrates are made up of simple sugar units (monosaccharides) like glucose.

* Breakdown: Cells can easily break down these sugar units through cellular respiration, releasing energy in the form of ATP (adenosine triphosphate).

* Availability: Carbohydrates are readily available in our diet from sources like grains, fruits, and vegetables.

While fats and proteins also provide energy, they are not as quickly accessible as carbohydrates. Fats are a more long-term energy source, and proteins are primarily used for building and repairing tissues.