Each Is True of Physiologic Roles and Reactions to Selenium,except

Each is true of physiologic roles and reactions to selenium,except one.Which is the exception?

A) Selenium functions mainly as a cofactor that protects membranes from oxidation.
B) It works hand in hand with vitamin E.
C) Deposition of large amounts during tooth formation enhance the mineralization process.
D) Excessive selenium prior to eruption may promote dental caries.