The correct answer is option one. The campaign in northern africa was so important to the outcome of the war as it helped the allies prepare for an invasion of Italy.
The North African Campaign began in June of 1940 and spanned for three years, as Axis and Allied forces pushed each other back and forth across the desert. At the beginning of the war, Libya was an Italian colony during many decades. Italy declared war on the Allied Nations in 1940. Italy invaded Egypt in September of 1940, and in a December counterattack, British and Indian forces captured some 130,000 Italians.