The perfect level

My daughter's company is currently looking for new staff. They have had problems in the past with employees who were too smart and who could not adapt to the common stupidity level of the company. Their new vacancy advertisement lists as first requirement:

* Ability to tell which is the largest island in the Baleares.

The really stupid people will not be able to find the answer. The really smart people will not bother applying for a position which such a silly requirement. And only the ones with the perfect stupidity level remains. Clever, isn't it?