Final answer:
A person who is planning to begin exercising soon and has taken steps toward it is in the preparation stage of change.
Step-by-step explanation:
In the context of behavior change, a person who is planning to begin exercising soon and has taken steps toward it is in the preparation stage of change. The stages of change model, developed by Prochaska and DiClemente, describes the different phases individuals go through when making a behavior change. In the preparation stage, people have the intention to take action within the next 30 days and have already started to take some initial steps towards their goal, such as researching exercise options or setting a start date.