【正确答案】 C

【答案解析】[听力原文]
   The number of Americans over the age of 65 is expected to double between now and 2030. This next generation of retirees will be the healthiest, best educated, and wealthiest in American history. But many of them won't have a retirement benefit their parents' generation fought hard to get. It is something known as a defined-benefit plan, or "pension." Retired workers who have a pension continue to be paid certain percentage of their highest annual salary—usually anywhere from one to three percent—multiplied by the number of years they worked for the company. Pensions first became popular during World War II, when a federally-approved wage-freeze meant unions had to negotiate for retirement benefits, instead of pay increases. Pensions reached the height of their popularity in the late 1970s, when more than 60 percent of Americans had one.
   What kind of benefit will the next generation of retirees not have?
此题问下一代退休人员无法享有何种利益。由画线句可知，下一代退休人员无法获得他们父辈努力争取得到的退休金。因此答案为C。retirement benefit意为“退休金”。