What was Thurgood Marshall's greatest contribution to the civil rights movement before he joined the Supreme Court? He argued successfully before the Supreme Court.
He registered new voting communities throughout the South.
He marched with protesters in Alabama.
He stopped a violent riot in Washington, D. C.

He argued successfully before the Supreme Court.

Explanation:

Thurgood Marshall was the first African-American to be a United States Supreme Court Justice. But most of all, he was also known for his activist works, fighting for the rights of blacks.

Before he became a Justice in the Supreme Court of the United States, Marshall was an activist and a lawyer fighting for the rights of the African American people. His famous success includes winning 29 Supreme Court cases out of the total 32 cases he was involved in.

Thus, the correct answer is the first option.

a) romans valued loyalty and discipline

d.summerains, the last one