I am listing both the Microsoft Office and the PC Engineering as choices on my application form. If I get rejected for one, will I automatically get rejected for the other?
No, there is no automatic rejection, though many people that are rejected for their first choice dont get into their second choice because the motivations that they write for access to the course are targeted towards their first choice.
We recommend that you submit a motivation for your second choice separately to your first choice, detailing why the course would still be appropriate to your career and personal development despite being on a different management track.