Answer:
B. He kept attacking an impenetrable front
Step-by-step explanation:
Burnside aggressive moves lead to his failure. Burnside tactics differ from McClellan's as Burnside was decisive and swift whereas McClellan's was slow. There were 120,000 troops with Burnside. Burnside army surrendered at Fredericksburg because they experienced delays in crossing Rapanhannock River. Lee army gained time and reunited and entrench themselves at Fredericksburg.