Which sentence lacks parallel structure?
a) we had a delicious breakfast of bacon and eggs and bread and butter.
b) a doll, a video, and a wagon were the items on the little girl's list.
eliminate
c) tonya and her friend tammy were studying biology and watching science films until late last night.
d) because he waited to the last minute to study, finished his labs too late, and is lacking motivation, jonathan failed science.