Which One of the Following Is the Best Example of Summative

Which one of the following is the best example of summative evaluation?

A) Ms.Vickers gives her social studies students a test at the end of a unit to determine how well they have learned the material in the unit.
B) Mr.Waters gives his history students a test at midterm to determine whether he needs to spend more time on certain aspects of Confederation.
C) Ms.Hurley gives her German students weekly exams to make sure they are keeping up with the material.
D) Before beginning a unit on water, Mr.Yanoshita gives his science students a pretest to determine how much they already know.