. >> ♪ look at the photograph ♪ >> nickelback takes the cake. ♪ what the hell is on joey's head. >> wordsop competition. ♪ >> and how long the words are matters, too, the hallelujahs and country music pitted out front led by carrie underwood. ♪ >> for the smartest lyrics of all number one songs, the highest average score goes to none other than mariah carey. ♪ >> well, i do love that tune. >> now, this is important to note about this study, it doesn't look at the depth like how deep and meaningful the lyrics are, it takes into accounts the length of a sentence. so, country music uses longer words -- >> like mississippi. >> talking about alabama and things like that. the syllables of the words. not the meaning. so, country is the absolute smartest genre. hip hop comes in on the lower scale. >> all right, thank you for bringing that to us, t.j. >>> we have, i don't know, jessie j, pretty smart to kick off our summer concert series, it's just moments away. ♪ >> coming up "gma's" summer concert series presented by copper coppertone. sunscreen. while providing protection from harmful uv rays.