A company has received state-of-the-art computers for the staff. Some of the employees who are older have made mistakes delaying the work process. How do you assess this situation? A) Employees need time and training to learn new computer programs; B) Older workers find it more difficult to use programs as fluid intelligence is declining; C) Older employees find it more difficult to use programs as crystallized intelligence is declining; D) Older workers show less concentration and this affects the mistakes they make