The battle in which lee decided to head north to try to attack the union was?

Battle of Gettysburg

Considering the overpowering victories that Confederates had secured at Fredericksburg and Chancellorsville Lee decided to invade the north. He believed that his soldiers uld feed themselves off the land given Pennsylvania's rich farmland and that this would relieve the Confederate war department from having to provide provisions.  

formulating the initial idea for the policy

answer is c.