Many Oklahomans grew to disapprove of the Vietnam War because Congress never officially declared war, the US military made little progress, and __________.A.they were unhappy that the US was not taking action to contain the expansion of communismB.they were angered that most men older than eighteen were required to register for potential service in the warC.they feared that the military would invade other neighboring nations, including ChinaD.they feared that communism would spread throughout Asia without US intervention