Explanation

A is correct because Aava Murto was a 16-year-old girl who briefly served as Finland's prime minister. B is incorrect because Yingluck Shinawatra is associated with Thailand and was not a 16-year-old PM of Finland. C is incorrect because Katrin Jakobsdottir is an Icelandic politician, not the person described in the question. D is incorrect because option A names the correct individual.