By the process of elimination, it is already not the last 2, so it is 50/50 chance to get it correct, but if you know how to add, you can figure out that 1 million per year in 5 years means that it is 12 million + 5 million, which is equal to 17 million and not 14,500,000. This brings it down only to 500,000$ salary increase per year
Posting screenshot of my answer in the linked question in case it gets deleted.