The answer is B, because with ADHD its a learning disability
Now Anxiety can be tricky because some can say that its a mental disorder when its not. Its a type of emotional feeling that can cause you to break out in to hives, you can have an Anxiety attack from feeling to over done with some thing and it can be almost anything that does it to you.
And an STD only happens if there's no protection when being sexual with someone of the opposite sex as you are (ie your boyfriend/girlfriend)
So, that only leaves the answer of B being the logical answer.