Answer: d) incorporate balance exercises if they are at risk of falling.
Explanation:
According to the physical activity guidelines of Americans in 2008 for older adults:
1. Older adults must perform the exercise that either maintain or improve their balance if they are at high risk of falling.
2. Older adults must understand how their chronic conditions affecting their ability to perform regular exercises.
3. Older adults should determine the level of effort they can put for the physical exercises and to achieve fitness.
4. Older adults must be physically active based on their ability and conditions allow.
