Which of the following best compares social developments in both west and East Africa?

Centralized power gave local governments less authority
Their king's hajj helped the poor in both regions
Islam became an important part of both societies
Trade with Arabs in both societies spread Islam

Islam became an important part of both societies and trade with Arabs in both societies spread Islam

The best comparison of social developments in both West and East Africa is that Islam became an important part of both societies and trade with Arabs in both societies spread Islam.

To determine which of the statements best compares social developments in West and East Africa, let's analyze each option:

1. Centralized power gave local governments less authority: This statement does not directly compare social developments in West and East Africa. It primarily focuses on the distribution of power within each region, rather than social developments.

2. Their king's hajj helped the poor in both regions: This statement suggests that the king's Hajj (pilgrimage) in both West and East Africa played a role in helping the poor. While it highlights a possible similarity in the actions of the kings, it does not provide a comprehensive comparison of social developments.

3. Islam became an important part of both societies: This statement suggests that Islam played a significant role in both West and East Africa, becoming an important part of their respective societies. This point compares a major religious development in both regions.

4. Trade with Arabs in both societies spread Islam: This statement implies that trade with Arabs in both West and East Africa had a significant impact on the spread of Islam. This point compares the influence of trade on Islam's dissemination in each region.

Based on the provided options, the statement that best compares social developments in both West and East Africa is "Islam became an important part of both societies." This statement highlights a common religious development that shaped the social fabric of both regions.