President Pierce's efforts to acquire Cuba for the United States caused which of the following? ...

President Pierce's efforts to acquire Cuba for the United States caused which of the following?
 
  a. Northern support for the liberation of Cuba allayed fears in that region that Pierce was controlled by theSlave Power.
 b. Some northerners concluded that Pierce was doing the bidding of the Slave Power.
  c. Support for such efforts by both northerners and southerners led to friendlier relations between the twosections of the country.
 d. Many southerners concluded that Pierce wanted to end slavery and colonize blacks in the Caribbean.