This was a system of a secret safe house and hiding places to aid runaway slaves to escape was called

Underground railroads

Explanation:

The Underground Railroad was a network of secret routes and safe houses established in the United States during the early to mid-19th century, and used by enslaved African-Americans to escape into free states and Canada. The scheme was assisted by abolitionists and others sympathetic to the cause of the escapees.

i think they would live in caves or natural tunnels

the correct answer is a) egypt and china.

egypt and china are two of the world’s oldest civilizations known by man. both ancient empires have left a great historic and cultural legacy to the world through archeology. both civilzations developed complex social relations, had deep religious beliefs, had dominion of agriculture and left writing records to understand their customs and culture.

among the requirements to consider a civilization, we find urbanization, writing records, a place of residence, agriculture methods, technological specialization, means of transportation, currency, population density, social stratification, and political integration.