An important philosophical idea during the Enlightenment was that the wealthy should give all of their money to the working poor.
monarchs should be granted a “divine right” to rule over their people.
the Catholic Church should exercise absolute rule over Europe.
ordinary people should be able to pursue greater opportunities.

The important philosophical idea during the Enlightenment Era was that  ordinary people should be able to pursue greater opportunities.

The Enlightenment Era was a period of great change in the world where scientific practices and thinking began in the late 17th century in the wake of the scientific revolution in the late Middle Ages.

The Period was characterized by the new ideas and discoveries that unveiled things that has been incomprehensible to man.

Hence, the Enlightenment Era was period of great human knowledge.

Therefore, the Option D is correct.

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An important philosophical idea during the Enlightenment was that  ordinary people should be able to pursue greater opportunities.

Explanation:

The Enlightenment was a period of great change in Europe and the United States in scientific practices and thinking that began in the late 17th century in the wake of the scientific revolution in the late Middle Ages. The Enlightenment lasted for about a century, and was characterized by the new ideas and discoveries that emerged during this period, which unveiled many things that had previously been incomprehensible to man. The Enlightenment was therefore a period of great human knowledge. This knowledge came about because man increasingly used scientific methods based on reason and realism rather than belief in supernatural forces or other babblings. The Christian Church was increasingly criticized after the new sciences and practices gave rise to a secular worldview.

c, to compete

porter is writing economic history because he is focusing on the cost of developing vaccines.