Primero, Eduardo se acuesta. Después [blank] translates to "First, Eduardo lays down. Afterwards [blank]". The options are as follows.
a. se duerme - "he goes to sleep"
b. se despierta - "he wakes up"
c. se afeita - "he shaves"
d. all of the above
Since Eduardo is going to bed, it's safe to infer that he won't be shaving. That eliminates options C and D. Between options A and B, B makes less sense than A; if he's just gone to bed, how would he be waking up immediately afterwards? Thus I conclude the correct option is A - se duerme.
Primero, Eduardo se acuesta. Después, se duerme. ("First, Eduardo lays down. Then, he sleeps.")