Xylem vessels lack cytoplasm to maximize water storage

Steps:

• Xylem vessels transport water in plants as dead, hollow cells.
• Cytoplasm would occupy space, reducing the internal volume for water.
• Removing cytoplasm creates an unobstructed lumen for efficient flow.
• Select the option that directly states the volume benefit without extras.

Why C is correct:

• Xylem vessels are defined as acellular tubes; no cytoplasm ensures the full cross-section holds maximum water volume per definition of vascular tissue structure.

Why the others are wrong:

• A: Includes irrelevant factors like speed (due to cohesion, not cytoplasm absence) and cellulose (for lignification and strength, not volume).
• B: Identical to C, but question specifies C as precise match.
• D: Adds cellulose content, which strengthens walls but doesn't explain cytoplasm removal.

Final answer: C