WHICH OF THE FOLLOWING BEST DESCRIBES THE AUTHOR'S ATTITUDE

70.

Which of the following best describes the author's attitude?

A.

Forgiving B. Surprised C. Vindictive D. ConcernedVII/. Read the following passage and mark the letter A, B, C, or D on your answer sheet toindicate the correct answer to each of the following questionsWhile most desert animals will drink water if confronted with it, for many of them theopportunity never comes. Yet all living things have water, or they will expire. The herbivoresfind it in desert plants. The carnivores slave their thirst with the flesh and blood of living prey.One of the most remarkable adjustments, however, has been made by the tiny kangaroo rat, whonot only lives without drinking but subsists on a diet of dry seeds containing about 5% free water.Like other animals, he has the ability to manufacture water in his body by a metabolic conversionof carbohydrates. But he is notable for the parsimony with which he conserves his smallsupply by every possible means, expending only minuscule amounts in his excreta and throughevaporation from his respiratory tract.Investigation into how the kangaroo rat can live without drinking water has involved variousexperiments with these small animals. Could kangaroo rats somehow store water in their bodies andslowly utilize these resources in the long periods when no free water is available from dew orrain? The simplest way to settle this question was to determine the total water content in theanimals to see if it decreases as they are kept for long periods on a dry diet. If they slowly use uptheir water, the body should become increasingly dehydrated, and if they begin with a store of water,this should be evident from an initial high water content. Result of such experiments with kangaroorats on dry diets for more than 7 weeks showed that the rats maintained their bodyweight. Therewas no trend toward a decrease in water content during the long period of water deprivation.When the kangaroo rats were given free access to water, they did not drink water. They did nibbleon small pieces of watermelon, but this did not change appreciably the water content in their bodies,which remained at 66.3% to 67.2% during this period.This is very close to the water content of dry-fed animals ( 66.5% ), and theavailability of free water, therefore, did not lead to any “storage” that could be meaningful as awater reserve. This makes it reasonable to conclude that physiological storage of water is not afactor in the kangaroo rat’s ability to live on dry food.