Final answer:
Proper body mechanics for bending involve bending the knees to reduce strain on the lower back, thus (A) is the correct answer.
Step-by-step explanation:
When it comes to performing a task that requires bending, such as picking up an object from the ground, proper body mechanics are essential to prevent injury. The correct answer is (A) Bending the knees, which demonstrates proper body mechanics. By bending at the knees and keeping the back straight, you maintain a strong posture that utilizes the leg muscles, reducing strain on the lower back. Bending from the waist, without bending the knees, puts unnecessary pressure on the back muscles and spine, increasing the risk of injury.