Direction: Read the passage carefully and answer the question that follows.

Today we are relishing the taste of modern scientific technology and applications. Science and technologies are a part of all human activities, from the houses that we live in, the food we eat, the cars we drive, and to the electronic gadgetry in almost every home that we use to remain informed and entertained. All this evidence show the blessings of scientific knowledge on humans.

Before the eighteenth century, we were plunged into the depths of ignorance and unawareness of scientific knowledge. Without having adequate scientific knowledge, our ancestors had buried their common senses deep under the mask of ignorant prejudices but it was the scientific revolution in the nineteenth century that unsheathed it and now we can see that the whole world is globalized due to this scientific revolution. 

Before the revolutionary changes in the early nineteenth century, health problems and a large number of fatal diseases gulped the whole community like a malicious dragon. The most common health problems were the numerous fatal diseases and epidemics. There was no cure for the most common diseases so these diseases always acted as a catastrophe. At that moment the average life span was thirty to forty years. Some common diseases like Chickenpox, Measles, Typhoid and many different kinds of fevers had killed more than the present American population in the last seven centuries throughout the whole planet. On the other hand, if we examine the ratio of mortality in the year 1999 in comparison with the past, we would come to know that these diseases couldn't affect more than some thousands of human lives.