Preterite is the normal past tense talking about events. Eg i went to the park with my sister = Fui al parque con mi hermana.
Fui in this case is the preterite
For imperfect it is what you used to do before but do not do any more. Usually ends in
aba
abas
aba
abamos
abais
aban
(for ar endings)
Option D is the correct option
