Question

what else has caused newtok to be an unsafe place to live?
causes
erosion is taking away newtoks land.
effect
newtok has become unsafe, and its people must move.
the air temperature often changes in newtok.
melting permafrost is making newtoks land weak.

Explanation:

The problem asks for another cause that has made Newtok an unsafe place to live. Among the given options, "Melting permafrost is making Newtok's land weak" is a valid cause related to environmental factors (since permafrost melting is an environmental change) that affects the safety of the living place.

Answer:

Melting permafrost is making Newtok's land weak.