The doctor gave me some advice on study ------ health.

选C,理由如下：
1 as well as 译为除…之外(也),既…又,在本句中,可翻译为：医生除了给我一些学习上的建议外还给我了有关身体健康方面的建议.
2 on study中的study前面需要有介词on,译为：在学习方面的建议.那么health前面当然也不能缺少介词on
综上所述,全句应该是：The doctor gave me some advice on study as well as on health