A Dilute Aqueous Solution Is to Be Concentrated in an Evaporator

A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because

A) Total heat transfer area of all the effects is -less than that in a single effect evaporator system
B) Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect
C) Boiling point elevation in a single effect system is much higher than that in any effect in a multi-effect system
D) Heat transfer co-efficient in a single effect is much lower than that in any effect in a multieffect system