<Table> Green tea <Tr> <Td_colspan="2"> The appearance of green tea in three different stages (from left to right): the infused leaves, the dry leaves, and the liquid . </Td> </Tr> <Tr> <Th> Type </Th> <Td> Tea </Td> </Tr> <Tr> <Th> Country of origin </Th> <Td> China </Td> </Tr> <Tr> <Th> Region of origin </Th> <Td> East Asia </Td> </Tr> <Tr> <Th> Ingredients </Th> <Td> Tea leaves </Td> </Tr> </Table> <Tr> <Td_colspan="2"> The appearance of green tea in three different stages (from left to right): the infused leaves, the dry leaves, and the liquid . </Td> </Tr>

What is the active ingredient in green tea