Answer:
I think "for this reason"
Explanation:
It sounds the best in a sentence using cause and effect.
The common misperception is : that it use a lot of water
Xeriscaping is a gardening method that reduces the need to use supplemental water from irrigation by creating a landscape that could sustain more water. It reduce the water usage of common gardening method.
Calpurnia wants to set a good example for the kids. When at church, she speaks just like anyone else there. I hope this helps!