Self-study
Those who have the ability to fully concentrate are always of above-average intelligence. █████ █████ ████████████ ███████ ██ █████████████ ████ ███████ ██ ███████████ ██ ██ █████████ ███████ ██ ████████████
Summary
Fully concentrate --> above-average intelligence.
Trained in speed-reading -most-> increased ability to concentrate.
Notable Valid Inferences
No clear inference to make up front. We're looking for a contradiction of one of the given facts. So, for example, an answer that says "someone can fully concentrate, but is NOT of above-average intelligence," would be false because it contradicts the first statement.
10.
If the statements above are █████ ████ ████ ██ ███ █████████ █████ ██ ████ ███████
a
Some people can ███████████ ███ ███ ████ ██ █████ ████████████ ███ ███ ██ █████████████ █████████████
This must be false. We know that all people who are able to fully concentrate are of above-average intelligence. So it's impossible for some people to be able to fully concentrate but be of below-average intelligence.
b
All people who ███ ██████████ ███ ██ █████████████ █████████████
This could be true. We know for sure that most speed readers have an increased ability to concentrate; but we don't know whether they have the ability to "fully" concentrate, or whether they are of above-average intelligence. It's possible all who can speed read are of above-average intelligence.
c
Many people of █████████████ ████████████ ███ ██████ ██ █████ ████████████
This could be true. We know that all people who can fully concentrate are of above-average intelligence, but this doesn’t mean that everyone of above-average intelligence can fully concentrate. So there can be many people of above-average intelligence who can't fully concentrate.
d
Some people with ██████ ███████ ██ ███████████ ███ ██ █████████████ █████████████ ███ ███ ███████████
This could be true. Although speed-reading is usually accompanied by "increased" ability to concentrate, that leaves open the possibility some people can speed-read but still have very little ability to concentrate.
e
All people who ███ ██████████ ███ ████ ██ ███████████ ██ ████ ███████
This could be true. We know that being trained in speed-reading is usually accompanied by increased ability to concentrate. It's possible everyone who can speed read can concentrate at least somewhat. Most of them experienced increased concentration, but this leaves open the possibility that everyone can concentrate at least a little bit.