D) supernatural forces, such as gods or monsters, that intervene
On the excerpt the narrator is describing Lugalbanda as a personal God who will help the hero with his mission. Epic poetry is known for the use of supernatural elements (like Gods, monsters, dragons and so on) that a worthy hero should stand against or help.
1) The author's main purpose is to persuade you through Ethos. Trying to give you a problem, then a solution, to show that he is fair. The author is trying to present these issues so that you are aware of what is going on. He is comparing it to various countries to show what they are doing and to encourage others to do the same. Explaining that the countries with the power and authority can help, being the more developed countries.
2) Pretty much the same as the first one, except, with the smoke health part, it is to portray how people need better way's to get fuel, or it will cost the country