In this task your given two statements. 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.

[EX Q]: I rubbed sandpaper on the wood.
The wood became smooth.
[EX A]: effect

[EX Q]: I missed the bus.
I was late to work.
[EX A]: effect

[EX Q]: The girl attended her classmate's birthday party.
She received an invitation.
[EX A]:
cause