That quiz seems obtuse to me and more than a bit absurd.
That said, dysgraphia/dyslexia often come along with ADHD. HOWEVER, 99% of properly taught dyslexic students can be fluent, accurate (at the sentence level), and easy readers, if they are taught decently. Most schools teach reading terribly, though! Unfortunately, dysgraphia is much, much more difficult to address. And dyslexia also is harder to deal with in math and science (where accurately reading arbitrary numbers is important) than in flowing text!
ADHD isn’t one condition. It could be labeled as a manifestation of a neurological abnormality. That manifestation could be caused by any of a number of underlying abnormalities. The autism-SPD-NVLD-PPD-NOS-clumsy child-sleep disorder-dyslexia-dyspraxia-dysgraphia-ADHD complex is one of those. No one probably has all those conditions at once, but many people have more than one. My sleep doctor insists that ADHD is usually a misdiagnosed sleep disorder. My psychiatrist insists that sleep disorders are often misdiagnosed ADHD. They’re both right. Heck, bipolar disorder is really a sleep disorder! Or there is a sleep disorder that causes bipolar disorder, if you want to look at it that way–a failure of the SCN. (I’m deadly serious about this–lithium works on the SCN, and that is the only way it works!)
There are lots of people who have ADHD without anything in that cluster. They have a different underlying neurological defect manifesting as ADHD.