Indelible means permanent. An indelible moment would be something like going to a job interview and the first impression you make is indelible, it can't be changed or redone.
The alien was able to defy the laws of gravity.
Hope this helped! (:
Word choice is used to get a point across. So if you look a choice A, the author definitely does not feel that the manufacturers are striving to provide COMPLETE information (or there wouldn't be the questions). I would say the same thing for D, making that an incorrect answer. Looking at B and C, the author does use exaggeration in personification, but he doesn't mention sales. He does however set a frustrated tone and touches on confusion of the customers, so I feel that C is the best answer here.
