Khartoum, Arabic Al-Khartoum city, executive capital of Sudan, just south of the confluence of the Blue and White Nile rivers. It has bridge connections with its sister towns, Khartoum North and Omdurman, with which it forms Sudan’s largest conurbation. Originally an Egyptian army camp (pitched 1821), Khartoum grew into a garrisoned army town. The Mahdists besieged and destroyed it in 1885 and killed Major General Charles George Gordon, then the British governor-general of the Sudan. Reoccupied in 1898, Khartoum was rebuilt by Governor-General Lord Kitchener and served as the seat of the Anglo-Egyptian Sudan government until 1956, when the city became the capital of the independent republic of Sudan.
"<span>c.Their current working conditions are quite difficult" would be the best option from the list, since this is saying that due to these hard conditions, they should try to find a home that makes life slightly less difficult. </span>
Since the North American continent is very diverse when it comes to physical geography, one of the main factors would be river flows and mountain chains affecting transportation routes within the continent, and oceans and mountain chains affecting rainfall that is vital for the crops.