听力原文：One of the most important questions a worker can ask is: "Will I have enough money for retirement？" For more than 30 years, Americans have used individual retirement accounts, or IRAs, to increase retirement savings. Today, there are several plans that let workers invest. The plans also offer tax savings.
The Employee Retirement Income Security Act of 1974 provided for the first IRAs. It set roles for retirement plans run by big businesses. Other measures provided for individuals who did not qualify for such plans, called pensions. The first kind of IRA is now called a traditional IRA. A worker can put up to 4,000 dollars of his or her yearly earnings into a special account. Workers over the age of fifty can invest 4,500 dollars. Unlike a pension, the saver controls the account and decides how it is invested. Money put in a traditional IRA is not taxed until it is withdrawn. But, savings cannot be withdrawn before the account holder is 59. 5 years old. If the money is withdrawn before that time, it is taxed like income and there is a 10 percent fine.
At first, IRAs were only for people not covered by pensions at work. But in 1981, everyone could open an IRA. Six years later, Congress banned highly-paid individuals from claiming tax reductions.
When were the first IRAs put into practice？
(30)

A. In 1930s.
B. In 1970s.
C. In 1940s.
D. In 1980s.