Transpiration in leaf mesophyll cells

Steps:

• Water enters leaf via xylem vessels in veins.
• Moves to mesophyll cells surrounding air spaces.
• Evaporates from wet cell walls into humid air spaces.
• Vapor diffuses out through stomatal pores.

Why C is correct:

• C labels mesophyll air spaces, where evaporation occurs as liquid water turns to vapor per transpiration process.

Why the others are wrong:

• A: Xylem transports water upward, no evaporation site.
• B: Phloem conducts sugars, unrelated to water loss.
• D: Stomata allow vapor exit, but evaporation precedes this in mesophyll.

Final answer: C