What Is the Difference Between Formative and Summative Assessment

What is the difference between formative and summative assessment?

A) Formative assessment is based on content; summative assessment is based on language.
B) Formative assessment is teacher-centered; summative assessment is student-centered.
C) Formative assessment is standards-based; summative assessment is content-based.
D) Formative assessment monitors progress; summative assessment is used to give grades.