The human race is spread all over the world, from the polar regions to the tropics. The people of whom it is made up eat different kinds of food, partly according to the climate in which they live, and partly according to the kind of food which their country produces. In hot climates, meat and fat are not much needed; but in the Arctic regions they seem to be very necessary for keeping up the heat of the body. Thus, in India, people live chiefly on different kinds of grains, eggs, milk, or sometimes fish and meat. In Europe, people eat more meat and less grain. In the Arctic regions, where no grains and fruits are produced, the Eskimo and other races live almost entirely on meat and fish
Answer Option (a) clearly stands out as the right answer choice. Options (b), (c) and (d) are only inferences from the passage and do not bring out the entire summary. Option (a) on the other hand, covers the entire scope of the passage. It offers the essence or the theme of the passage while others offer merely citation.