Answer:
The general purpose is to persuade.
Explanation:
A speech can have three general purposes: to inform, to persuade/motivate, and to entertain. Betty's purpose is clearly not to simply entertain her employees, to amuse them. She is a manager addressing an issue, not a comedian aiming for laughs and fun. She is also not just informing her employees. They have already been informed on the issue, which is the new security policy for the company computers. Betty's purpose is to persuade them that the new policy is necessary, important, and must be followed by everyone. They do not appreciate the inconvenience of the change, so she must convince them that such inconvenience is a small necessary evil that will bring larger benefits.