Read this partial summary of Passage 1.It has been known since ancient times that people behave oddly when the moon is full. The
moon's gravity may be the cause. Which sentence could be added to complete the
summary?

The full moon causes dogs to bite people more
often.

This effect is the reason extra police officers may
be needed

Modern studies now confirm a lunar effect on
human behavior.

Four out of five mental health professionals could
not be wrong