His long_____ public service earns him respect across the country.
A、appreciation of
B、responsibility for
C、obligation to
D、commitment to
【正确答案】：D
【题目解析】：此句话的意思是他长期献身于公共服务的行为，为他赢得了全国人民的尊敬。“commitment （to sb/sth）”表示（对工作或某活动）献身，奉献，投入；“appreciation of sth”表示理解，感谢或者鉴定；“responsibility for”表示对...负责；“obligation to”表示义务，职责。