VERMILLION, S.D. (AP) — The spokeswoman for the University of South Dakota says a USD billboard with a grammatical error reflects badly on the university.

The billboard along Interstate 90 west of Sioux Falls quotes Forbes magazine saying USD is the "Best in the Dakota's." An apostrophe is misplaced in the word "Dakotas," making the word possessive rather than plural.

USD spokeswoman Tena Haraldson says the mistake was human error — the wrong version of a design got sent to the billboard company.

After people began talking about the billboard and posting pictures on social media, USD responded with a tweet telling people they "passed this grammar quiz," and saying a new billboard is planned.

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