You Have Just Been Hired as the New Assistant Human

You have just been hired as the new Assistant Human Resources Manager at your firm, having worked your way up from the factory floor to the administrative suite.  During your briefing for the new job, you are told that the firm has learned that its employees are attempting to unionize, a move which the firm has vowed to fight. As part of that effort, your boss, the HR Manager, has asked you to privately talk to some of your former co-workers on the factory floor to see what their thinking is, to learn about how many are in favor of unionizing, who, specifically, is supporting it, and what might make them change their minds.  Among the things they want to know is what would work better - threats of reprisals against those supporting a union, or promises of benefits to those who oppose it. You are eager to do well at your new job, but you see some problems with these requests.  Of the following choices, which is your best option?

A) do as they ask; none of it is illegal
B) tell them you can't do what they ask because it is illegal
C) tell them you would be glad to talk informally with your former co-workers to find out their attitudes about unionization and why this has come up, but that speaking about reprisals and benefits would be an unfair labor practice