I believe the answer to this is C.
Satan uses our 'fleshly weakness' to lead us into temptation. The first temptation Jesus faced in the wilderness was 'the lust of the flesh'. Just as it was then, in today's world this is the desire of material things such as food, clothing, money, etc. instead of trusting God for our provision of these things, specifically the 'spiritual food's that only God can give!
The previous route was very dangerous and was also expensive to traverse. Early travelers encountered dangers such as war zones and diseases. They also had to cross deserts and mountains to get to their destination. Progress was made when a new route via the sea was discovered. This limited the perils that were once faced.
