A—catalogue price
B—-Central Bank
C—consular visa
D—life insurance
E—life cycle
F—Letter of Credit
G—sales department
H—sales promotion
I—wholesale price
J—wholesale trade
K—working condition
L—business and economy
M—information and technology
N—life expectancy
O—working capital
( )人寿保险 ( )促销

A. why "Good Morning to All" was replaced by "Happy Birthday to You"
B. how the song "Happy Birthday to You" was composed
C. the history of the song "Happy Birthday to You"
D. why the song "Happy Birthday to You" is popular