Henri Rousseau and Grandma Moses both produced ____ art (5)

I believe the answer is:

naive

(Other definitions for naive that I've seen before include "Jejune" , "Unaffected or guileless" , "Lacking wisdom and judgement" , "Unsophisticated and gullible" , "Simple, innocent or unsophisticated" .)

I've seen this clue in The Times.

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