Cellulose's structural features for rigidity and strength

Steps:

• Identify cellulose as a linear polymer of β-D-glucose linked by β-1,4-glycosidic bonds, forming straight chains.
• Recognize that hydrogen bonding between chains creates microfibrils for tensile strength.
• Note unbranched structure allows tight packing, essential for plant cell wall support.
• Eliminate features like branching, which would weaken the structure and not contribute to function.

Why C is correct:

• Features 2 (hydrogen bonding) and 3 (unbranched chains) enable parallel alignment and cross-linking, providing mechanical strength per polymer chemistry principles.

Why the others are wrong:

• A includes 1 (e.g., α-linkages), which form flexible helices in starch, not rigid cellulose.
• B pairs 1 with 3, but 1 disrupts straight-chain formation needed for function.
• D omits 3, as hydrogen bonding alone insufficient without unbranched packing for stability.

Final answer: C