Readers challenge a writer's text when they:
a. refuse to read.
b. lend the text to others.
c. question the writer's opinions.
d. proofread articles to make them more accurate

Readers challenge a writer's text when they question the writer's opinions. It is normal that your opinion is not the same as the author's, and it should be like that, you should always question and think about everything.

A broken relationship can be fixed if the right channels of communication are provided. In case the author wants to show his or her friends that there is a possiblility to mend things, the bridge between them would be the best object to simbolize the means to work out the broken relationship. Figuratively, the bridge can create the path which will take each part to the other side to overcome past difficulties. The right option is C.