Species of the genus Bifidobacterium

Species of the genus Bifidobacterium produce lactic acid and historically have been considered Lactic Acid Bacteria (LAB) even though they differ from all other LAB species by what characteristic?

a.Bifidobacteria are cocci whereas all other LAB are rod-shaped

b.Bifidobacteria belong to the phylum Actinobacteria

c.Bifidobacteria require bile salts

d.Bifidobacteria form spores

e.Bifidobacteria have low G+C percentages in their DNA