Based only on the information provided above, which one of the following statements can be logically inferred with certainty?

To determine which statement must logically follow with certainty:

1. Premise Analysis:

   • Cause of health issues: A complete lack of physical exercise among the working population.

   • Action taken: To address the issue of lack of physical exercise causing health problems, the Government decided to incentivize riding bicycles to work.

2. Evaluating Options:

   • Option A: It claims *all* of the working population will henceforth ride bicycles. Providing monetary incentives does not guarantee that everyone will comply. Hence, this cannot be inferred with certainty.

   • Option B: It claims riding bicycles will ensure that *all* of the working population is free of health issues. Lack of exercise was only "one of the leading causes", not necessarily the only cause, and riding bicycles cannot guarantee complete eradication of all health issues.

   • Option C: The passage states that health experts concluded the lack of exercise was a cause; it does not state that the experts suggested making bicycle riding mandatory.

   • Option D: Since the Government introduced bicycle riding incentives specifically as a measure to tackle the health issues stemming from a lack of physical exercise, the Government must believe that bicycle riding constitutes a form of physical exercise.

Thus, D is the only statement that can be logically inferred with certainty.