Final answer:
The main social developments in the Hellenistic world included the philosophical shift towards personal ethics, the emergence of new religions promising personal salvation, the amalgamation of Greek and local cultures, and the expansion of Greek cities as cultural hubs. Social stratification between Greeks and non-Greeks was prevalent, leading to periodic tensions. The correct option is A.
Step-by-step explanation:
The Hellenistic period was marked by significant social developments, most notably the blending of various cultures and the shift in focus to personal happiness. Philosophers of the era departed from Classical Greek ideals to pursue ethical and tranquil lifestyles through schools of thought such as the Epicureans, Stoics, and Cynics. This era also saw the rise of mystery religions that catered to personal fulfillment.
New cities founded by Alexander the Great and his successors flourished as centers for Hellenistic culture, which was a mix of Greek traditions and local customs. These cities featured Greek-style amenities like theaters and temples. Citizenship evolved from a political to a more elitist status, and the growth of Greek cities in formerly Persian lands saw the creation of Grand cities like Alexandria in Egypt, complete with Greek cultural institutions.
Despite these advancements, there was a distinct division between the Greek ruling class and the indigenous non-Greek populations, leading to social stratification and periodic rebellions. Knowledge and ideas expanded significantly during this period, but there were fewer correspondences to advances in technology or engineering.