The era of one-oarty domination that began in 1968 was different from past eras of one-party domination because

a. the Republican party gained no new members in Congress.

b. the Democratic party gained no new members in Congress.

c. one party controlled Congress while the other controlled the presidency.

c. minor parties interferred with the power of the Republican party.

I am confused.

http://en.wikipedia.org/wiki/U.S._presidential_election,_1968
http://en.wikipedia.org/wiki/United_States_House_election%2C_1968

All of the information is readily available on the web.