Final answer:
Encourage an older adult to be physically active by suggesting small steps, such as moving for just 5 minutes.
Step-by-step explanation:
To encourage an older adult to be physically active when they are unsure about meeting the time requirements, it would be best to make a statement that emphasizes starting with small steps. One appropriate option could be 'How about just moving for 5 minutes? Let's walk together outside.' This statement suggests a simple and achievable activity that can be done in a short amount of time. By starting with a small duration, the older adult can gradually increase their activity level over time.