This is a question with answer options. Goal: To save on buying water,

Which of the following methods is more reasonable for accomplishing this goal?

OPT: * use a rain catcher such as a barrel and route the roof gutters to it, then purify the collected water.. * use a rain catcher such as a barrel and route the roof gutters to it, then drink the collected water.....I think the answer is
use a rain catcher such as a barrel and route the roof gutters to it, then purify the collected water.