What were the primary work of mainframe computers in the 1950s through the 1960s?

In the 1950s and 1960s they dominated the computer science area in large corporations. Mainframes are capable of delivering processing services to thousands of users through thousands of terminals connected directly or across a network. They were widely used in war for ballistic calculations

legislative branch:

one of the three branches of government divided between the senate and the house of representatives.

- creates or makes laws

- power to override a veto

executive branch:

one of the three branches of government, headed by the president.

- enforces or carries out laws

- power to veto a bill sent to it by congress

judicial branch:

one of the three branches of government, headed by the chief justice of the supreme court.

- interprets laws

- power to declare laws or actions by the government unconstitutional

i think the answer is b.