What conditions in the roman empire allowed christianity to grow while the empire declined?

i think the answer is the one about environmental and social health.

hope this

the right answer is the third one: turnpikes went short distances to connect markets. turnpikes, also known as toll roads, were very important for trade and transportation (of people, goods and products) in the 19th century, coinciding with the expansion towards the west. they contributed significantly to the economic development of the united states.