A new clinical trial reports that a specific exercise program reduces chronic lower-back pain in adults. The participants, however, were healthy office workers under fifty with no history of injury or surgery. Whether the program's benefits extend to older adults, those recovering from injury, or people with desk-bound vs. physically demanding jobs has not yet been studied.
Which choice best describes the function of the third sentence in the text?
- Acheck_circle
It restricts the scope of the result by enumerating populations the trial did not cover.
- B
It introduces a different exercise program.
- C
It defines the term 'lower-back pain'.
- D
It generalizes the result to all adults.
Explanation
The third sentence specifies who has not been studied yet. B captures this scope-restriction function.