Final answer:
The 1965 Voting Rights Act is the best explanation for a trend reflecting the enforcement of expanded voting rights, as it enforced the Fifteenth Amendment and combat voter suppression. The correct option is a) The Voting Rights Act
Step-by-step explanation:
The best explanation for the trend reflected in the table pertaining to the expansion of voting rights and its enforcement would be the 1965 Voting Rights Act. This act was intended to enforce the provisions and intent of the Fifteenth Amendment, which aimed to bar race as a reason for denying any US citizen the right to vote.
The law empowered the federal government to oversee elections and intervene to protect voters' rights, effectively making it a landmark in the fight against voter suppression and in promoting political participation. The correct option is a) The Voting Rights Act