In the following passage some of the words have been left out. Read the passage carefully and select the correct answer for the given blank out of the four alternatives.
One of the major problems of India is unemployment. Unemployment means the state of being without _______ opportunity of earning one’s livelihood. In the good,old, golden days when the population of the world was _______, there was hardly a person who was not employed in some way or other to earn a _______. But this situation no longer exists. In those days most people lived in the rural areas and depended on agriculture and cottage industries. But industrial _______brought about a change in the situation. It introduced machines, and as a single machine can do the work of many men, it naturally threw many persons out of employment. No doubt, this industrial civilization has greatly _______ the wants of and opened up many new opportunities for employment.