The right answer is C. despertarse
despertarse means to wake up. This is the first thing someone does before doing anything else. Another translation to this word is to get up. This translates the same into Spanish. So, some sentences using this word are:
a. Pedro tiene que despertarse antes para ir al trabajo (Pedro has to get up before going to work)
b. Anita tiene que despertarse ya porque se le hará tarde para ir al colegio. (Anita has to wake up right now becuase she's going to be late to go to school)