Large global wind systems are created by the uneven heating of the Earth's surface. ... Unequal heating of the Earth's surface also forms large global wind patterns. In area near the equator, the sun is almost directly overhead for most of the year. Warm air rises at the equator and moves toward the poles.
because they're different ways
Question A
Correct option is (iii) sought after, as it is indicated in the passage that "I was overwhelmed with gratuitous advice". Gratuitous means not required, or not necessary. Hence the author was not asking for advice, it was not sought after
Question B
Correct option is (iv) when he was on the steamer. It is indicated at the end of the passage that "The fellow passengers in the steamer began to advise us". After reading the statement, "I should want them after leaving Aden", you might feel that the correct option could be (ii) when he was in Aden, but the passage doesn't give enough information to confirm that the advice was give at the point when he was in Aden
Question C
The correct option is (iii) meat-eating would keep him healthy. It is indicated in the passage that "The majority of them said I couldn't do without meat in the cold climate. I would catch consumption.". Hence, the meat was supposed to keep him healthy and not catch consumption.
Question D
The correct option is (iv) he had promised his mother he would not do so. It is indicated in the passage that "My mother, before consenting to my departure, had exacted a promise from me not to take meat. So, I was bound not to take it, if only for the sake of the promise.".