Which statements describe the effects of the 26th amendment

The long debate over lowering the voting age in America from 21 to 18 began during World War II and intensified during the Vietnam War, when young men denied the right to vote were being conscripted to fight for their country. In the 1970 case Oregon v. Mitchell, a divided U.S. Supreme Court ruled that Congress had the right to regulate the minimum age in federal elections, but not at the state and local level. Amid increasing support for a Constitutional amendment, Congress passed the 26th Amendment in March 1971; the states promptly ratified it, and President Richard M. Nixon signed it into law that July.