Who of the following is the smartest?

I cannot really choose, I mean it is difficult to determine an answer for this question without having any background information. I mean, I can deduce from the amount of education and professional training that an individual who has acquired the professional titles as written in B/C/D would have to be fairly "smart". However, asking such a question without clearly defining "smart" leaves the door open for answers that derive purely from the stigmas that are attached to each of the options, which in short, does little.....blah blah blah...in determining who is the smartest....lmfao