I'm ENTP-A on this exam. I've always known I was ENTP, but I think when I was younger I came up type B.
16 personalities is like a Big5 test disguised as MBTI, I advice to not use it
MBTI and Big 5 aren't really that different. Perhaps the scientific community prefers Big 5 because it also evaluates Neuroticism? MBTI only has 4 factors. Either way, they are both built from the work originally done by Carl Jung.
Personally I prefer Strengths Finder 2.0. If a person really wants to know about themselves in a specific way, I find Strengths Finder to be the most specific.