The four aspects are consists of : one should be sensitive towards the audience’s needs, adapting “you” attitude, Maintaining standards of Etiquette – emphasizing the positive to avoid negative language and be honest not harsh; should be respectful, tactful and talk with diplomacy, Using Bias-Free Language, building a strong relationship with the audience by establishing credibility.
Answer: What is the other motorist likely to do in response, according to the authors of your text:
The other motorist is likely to accept the apology and maybe collect a token fee for repairs.
Explanation: This is because according to the text above which says "It's my fault; I should have been paying closer attention to driving. I'm sorry." That statement alone shows the true sincerity in the apology which would calm the tension or anger of the other motorist. And the matter would likely to be solved amicably.