Socialism does not work because it is not consistent with fundamental principles of human behavior. The failure of socialism in countries around the world can be traced to one critical defect: it is a system that ignores incentives. Under socialism, incentives either play a minimal role or are ignored totally.
Answer:
Commas indicate a natural pause in the sentence.
The use of the term "National Republican" dates from 1830. Henry Clay served as the party's nominee in the 1832 election, but he was defeated by Jackson. The party supported Clay's American System of nationally financed internal improvements and a protective tariff.
It would be a or d because it was during in the byzantine time