Why should a writer include personal experience as evidence?
a. to enhance credibility
b. to express facts as numbers
c. to quote an expert
d. to establish a focus select the best answer from the choices provided a b c d

I believe the answer is: a. to enhance credibility

Personal experience would give the readers with a certain level of assurance that the writers at least know what they are talking about.

For example, let's say that there are two authors of a self defense book. The first author has an experience as a president's bodyguard while the second author is a full time web designer. Most people would most likely see the first author as the more credible one.

i think it is the third one.