Yes, this was easy to answer. But I suspect that among all those who answered correctly, there would be a good percentage who may not follow the stated practices, especially the one about redundant processes. It's so easy to just code up your calculation or validation without looking to see if it's already done somewhere else, maybe somewhere not isolated as a separate module.

The lesson of this QOD may not so much be "know these best practices", but "think about whether you and your team follow these best practices". Otherwise, it would be like asking "Does a stop sign mean come to a full stop and checking for clear passage before proceeding?". I'd guess that 95% of drivers would answer "yes" on a license test, but how many actually do that?