A. books[0:2],输出:['半生缘','往事并不如烟', '心是孤独的猎手']

B. books[0:2],输出:['半生缘','往事并不如烟']

C. books[:2],输出:['半生缘','往事并不如烟']

D. books[-2:],输出:['往事并不如烟','心是孤独的猎手']