Which of the following occurred after allied forces invaded the italian mainland in september 1943?
a, german forces retreated from italy.
b. axis forces repelled the allies.
c. italian forces quickly surrendered.
d. allied forces declared victory in europe.

The answer is B, Italian forces quickly surrendered. Troops and vehicles being arrived under shell shoot amid the intrusion of territory Italy at Salerno, September 1943. The Allied attack of Italy was the Allied land and/or water capable arriving on terrain Italy that occurred on 3 September 1943 amid the early phases of the Italian Campaign of World War II.