Concept:Transpiration rises when plants have greater exposed leaf surface or a steeper water vapour gradient.
Explanation:Fewer stomata per unit area would lower the number of pores for water loss, so transpiration decreases.
Higher humidity around the leaves reduces the difference in water vapour concentration, slowing transpiration.
A larger leaf surface area to volume ratio gives more surface through which water can escape, increasing transpiration.
Removing leaves cuts down the total transpiring surface, which reduces transpiration.
Thus, the only factor that directly increases transpiration is the increase in leaf surface area to volume ratio.
Answer:C. An increase in leaf surface area to volume ratio