Which of the Following Is the Most Likely Sequence of Events,from

Multiple Choice

Which of the following is the most likely sequence of events,from earliest to most recent,in the evolution of sponges (organisms with many cells that have different functions) ?
1) single-celled eukaryote
2) single-celled prokaryote
3) multicellular eukaryote
4) colonial eukaryote

A) 2,1,4,3
B) 2,1,3,4
C) 1,2,3,4
D) 1,2,4,3