Answer:
Preparation.
Explanation:
The Stages of Change Model is a model theorized by James O. Prochaska and Carlo DiClemente in 1983.
According to this theory, stages are defined for the people who want to change their addictions or certain habits.
Prochaska and DiClemente had defined six stages of change model:
The stage at which 'new client' is, is 'Preparation stage'.
According to this stage, a person who wants to change decides to change within a month.
In the given case, the new client had decided to try a different approach to exercising to become a regular exerciser.
So, the correct answer is "Preparation stage".