题目选项分析

Although she had been known as an effective legislator first in the Texas Senate and then also later in the United States House of Representatives, not until 1974 did Barbara Jordan become a nationally recognized figure, as she participated in the hearings on the impeachment of President Richard Nixon, being televised nationwide.

Although she had been known as an effective legislator first in the Texas Senate and later in the United States House of Representatives, Barbara Jordan did not become a nationally recognized figure until 1974, when she participated in the hearings on the impeachment of President Richard Nixon, which were televised nationwide.