The correct choice from given option is "D", "Lactobacillus"
It seems proper to explain a bit about the types of cells here. Two type of cells are:
1) Prokaryotic: these cells have no nucleus and they are small and simple.
2) Eukaryotic: These cells have a nucleus and are large and complex as opposed to prokaryotic.
"Lactobacillus" belong to first stated category here.