Directions: Read the passage given below and answer the questions that follow by selecting the correct/most appropriate options : As science progresses, superstitions ought to grow less. On the whole, that is true. However, it is surprising how superstitions linger on. If we are tempted to look down on savage tribes for holding such ideas, we should remember that even today, among most civilised nations, a great many equally stupid superstitions exist and are believed in by a great many people. Some people will not sit down thirteen at a table; or will not like to start anything important on a Friday; or refuse to walk under a ladder. Many people buy charms and talismans because they think they will bring them luck. Even in civilised nations today, many laws are made on the basis of principles which are just as much unproved. For instance, it is often held as a principle that white people are by nature superior to people of other colours. The ancient Greeks believed that they were superior to the people of Northern and Western Europe. The only way to see if there is anything in such a principle is to make scientific studies of a number of white and black and brown people under different conditions of life and find out just what they can and cannot achieve. It is, however, true that the increase of scientific knowledge does reduce superstition and also baseless guessing and useless arguments and practices. Civilised people do not argue and get angry about what water is composed of. The composition of water is known, and there is no dispute about it. Which part of speech is the underlined word in the following sentence ? On the whole that is true.