Actuary is not that hot anymore. I would advise her to get into finance if that's what she's interested in, and career wise, she'll have more choices.
I don't agree with paying too much attention to the future career at her age, and like 开喜 said, it's best to just follow the heart, study what really interests her. I've known many talented people who started out in completely different field, and gradually worked towards their career goal. Smart people will fit in just well anywhere, it's more important to get the foundations built properly. By foundation, I would actually emphasize on social skills, communication skills, problem solving skills, analytical skills, skills to conduct independent researches, and not necessarily a particular set of knowledge.