Final answer:
The nurse aide should use proper body mechanics by bending the knees and keeping their back straight (option C) to lift a client safely, which engages stronger leg muscles and reduces back strain.
Step-by-step explanation:
The correct method for a nurse aide to use when preparing to lift a client using proper body mechanics is option (C) bend knees and keep back straight. This approach is based on the principles that emphasize protecting the spine by minimizing the forces exerted on it. By bending the knees, the nurse aide lowers their center of gravity, which increases stability. Additionally, keeping the back straight engages the stronger leg muscles instead of the weaker back muscles, reducing the potential for injury. It's essential to ensure that feet are positioned apart to provide a wide base of support, enhancing balance when lifting.
Incorrect techniques, such as lifting with the back or holding the object away from the body, can create excessive force on the spine, resulting in strain or injury. Instead, the nurse aide should lift using the leg muscles, which are more robust and can handle heavier loads without compromising the back's integrity.