The human body uses __ for fuel and energy.

• A. Complex Carbs
• B. Fats
• C. Proteins
• D. Vitamins

Answer: (A)

Carbohydrates serve as the body's main source of fuel for energy. When you consume complex carbohydrates, they’re broken down into glucose, which cells burn to produce ATP—the immediate energy currency the body uses for most activities. Complex carbs provide energy more steadily because their digestion is slower than that of simple sugars, helping keep blood glucose levels balanced and preventing quick energy crashes. Fats are also energy-rich, but they’re mainly tapped for longer, lower-intensity activity and are slower to mobilize. Proteins mostly build and repair tissues, and vitamins don’t supply calories or usable energy themselves. So, complex carbohydrates are the best fit for fueling the body and providing energy.