A company is testing whether the number of hours employees spend on training each month affects their monthly productivity index. The company selects 45 employees at random from all its employees. The table summarizes the data for the 28 employees who received at least 4 hours of training in a month.
| Hours of training | Productivity \lt 70 | Productivity | Total |
|---|---|---|---|
| 4 to 6 hours | 3 | 7 | 10 |
| More than 6 hours | 2 | 16 | 18 |
| Total | 5 | 23 | 28 |
What is the largest group to which the results of this study can be generalized?
The 28 employees who received at least 4 hours of training
The 45 randomly selected employees
All employees in the company
All employees with a productivity index
