Task: Class Definition Understanding (ontology: Sciences/Biology)

Which of the following definitions best describes 'alpha-D-GalNAc-(1->2)-[alpha-D-Glc-(1->3)]-beta-D-Man-(1->4)-[beta-D-Glc-(1->2)]-alpha-D-Man-(1->5)-alpha-Kdo'?

A. A branched amino hexasaccharide comprising a tetrasaccharide backbone consisting of alpha-D-galactose, beta-D-galactose, N-acetyl-beta-D-glucosamine and N-acetyl-D-galactosamine residues linked in sequence (1->3), (1->4) and (1->3), with alpha-L-fucose residues linked to the beta-galactose and N-acetylglucosamine via (1->2) and (1->3) linkages respectively.
B. A six-membered glucosamine oligosaccharide consisting of two repeating units of beta-D-Gal-(1->4)-[alpha-L-Fuc-(1->3)]-beta-D-GlcNAc joined by a (1->3)-linkage.
C. A branched amino hexasaccharide consisting of a linear chain of a N-acetyl-alpha-D-glucosamine residue, two L-glycero-alpha-D-manno-heptose (Hep) residues and a 3-deoxy-alpha-D-manno-oct-2-ulosonic acid (Kdo) residue in a (1->2), (->3), (1->5) sequence, to the Hep residue nearest to the Kdo is linked also (1->4) a beta-D-glucose residue, with the Kdo residue also carrying a further Kdo residue linked (2->4). Corresponds to a fragment of an inner core lipooligosaccharide epitope from Neisseria meningitidis.
D. A branched amino hexasaccharide corresponding to the core oligosaccharide of the Gram negative bacterium Francisella tularensis.

Answer: A branched amino hexasaccharide corresponding to the core oligosaccharide of the Gram negative bacterium Francisella tularensis.