What were effects of the Ostend Manifesto and the caning of Charles Sumner? A) The South agreed that the secrecy of the manifesto and beating of a senator were both wrong.
B) The South gained more land in Cuba to expand slavery and silenced a northern senator.
C) Northerners were outraged that the South had used such methods in support of slavery.
D) Northerners were outraged that the South had invaded Cuba and killed a U. S. senator.