The passage below has gaps numbered 11 to 20. Immediately following each gap, four options are provided. Choose the most appropriate option for each gap. It...

  It is business of the scientist to accumulate knowledge about the universe and all that is in it and to find if he is able, common……11…..[A. experiment B. instruments C. approaches D. factors] which underlie and account for the facts that he knows. He chooses when he can, the method of the controlled…….12…..[A. respondent B. experiment C. system D. data]. If he wants to find out the effect of light on growing plants, he takes many plants, as alike as possible. Some he stand in the sun, some in the shade, some in the dark, all the time keeping all other

  In the course of his……18…..[A. finding B. queries C. experiment D. inquiries], the scientist may find what he thinks is one common explanation for an increasing number of facts the explanation, if it seems consistently to fit the various facts, is called…….19……[A. an antithesis B. a principle C. a thesis D. a hypothesis]. If this continues to stand the test of numerous experiments and remains unshaken, it becomes a……20…..[A. deduction B. law C. notion D. thesis].