In this task your given two statements in Chinese. You must judge whether the second sentence is the cause or effect of the first one. Label the instances as "cause" or "effect" based on your judgment. The sentences are separated by a newline character.
--------
Question: 我改变了谈话的话题。
谈话变得紧张起来。

Answer: cause


Question: 班上的每个人都瞪着这个学生。
这个学生的电话响了。

Answer: cause


Question: 这男人变老了。
他的头发变灰了。

Answer:
effect