Which of the following might undermine the at$-$will employment relationship?

Question $5$ options:

a$)$

A CEO saying to a candidate, $"$If you make a one$-$year commitment to the company, we'll give you that long to turn the department around."

b$)$

A company policy that states all first time disciplinary issues will result in a written warning.

c$)$

A manager telling someone that the company would like to promote them into a particular position if they improve their communication skills.

d$)$

All of the above

e$)$

None of the above