B - Climate

A - Christianity
B - The Permafrost makes the construction of roads and buildings difficult

100% :)

Based on the given information, it seems like you are presenting a statement with two different topics: climate (represented by B) and Christianity (represented by A). Additionally, you mention that the permafrost makes the construction of roads and buildings difficult. However, it is unclear how these elements are related or what specific question you are asking. Could you please provide more context or clarify your question?