单项选择题

"How did you do it, Dad How have you managed to not take a drink for almost 20 years" It took me almost 20 years to have the 1 to even ask my father this very personal question. When Dad first quit 2 , the whole family was on pins and 3 every time he got into a situation that, in the past, would have started him drinking again. For a few years we were afraid to 4 it up for fear the drinking would begin again.
"I had this little 5 that I would recite to myself at least four to five times a day," was Dad"s 6 to my 18-year-old unasked question. "The words were an instant relief and constant 7 to me that things were never so 8 that I could not handle them," Dad said. And then he 9 the poem with me. The poem"s simple, yet profound words 10 became part of my daily routine as well.
About a month after this talk with my father, I received a 11 in the mail from a friend of mine. It was a book of daily affirmations with one affirmation 12 for each day of the year.
It has been my 13 that when you get something with days of the year on it, you automatically turn to the 14 that lists your own birthday.
I hurriedly opened the book to November 10 to see what 15 of wisdom this book had in store for me. I did a double-take and tears of disbelief and appreciation rolled 16 my face. There, on my birthday, was the exact 17 poem that had helped my father for all these years! It is 18 the Serenity Prayer: God, grant me the Serenity to 19 the things I cannot change; the Courage to change the things I can; and the 20 to know the difference. Living one day at a time, enjoying one moment a time.

A.principles
B.understandings
C.experience
D.proverbs