One Principle of Usability Testing Is That It Permeates Product

Multiple Choice

One principle of usability testing is that it permeates product development. What does that mean?

A) Designers and managers know that if a product fails the usability test given right before product launch, they will not be paid.
B) Once a product is permanently on the market, you no longer need to test it.
C) Conduct testing on prototypes, then conduct evaluations on final drafts.
D) You conduct testing in all stages of a product's development, not only at the end.