Which statement is a counterexample to:

"All basketball players are more than 6 feet tall."

Always when we have a statement like:

"all of {some group} have {a given property}"

A counterexample of this is:

"There exists at least one element of the given group that does not meet the property"

Then we have the statement"

All basketball players are most than 6 ft tall

The counterexample would be:

There exist one basketball player that measures 6ft

or

There exist one basketball player that measures less than 6ft

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