To Infinity and Beyond

There appear to be minor variations from chart to chart for OBAFGKM charts on the internet, where it concerns what color stars are. For example, some charts list Type A stars as white, some list them as blue-white. Some charts list type M stars as red, some list them as orange-red. I understand that there’s probably some room for interpretation, but can you tell me if there’s a definitive chart that you’ll be using to score the tests? Thank you!!
The minor variations will not make a difference. For example, I could imagine asking something like
 – True or False – O stars are bluer than K stars.
 – or, order the following four star types in order of decreasing temperature A, F, M, O
So no subtle gradations of color are required, just a broad brush view of the sequence and that the bluer colors mean higher temperatures.