<Tr> <Td> Perl </Td> <Td> $a = = $b </Td> <Td> $$a = = $$b </Td> <Td> when $a and $b are references to scalars </Td> </Tr> <Tr> <Td> PHP 5 </Td> <Td> $a = = = $b </Td> <Td> $a = = $b </Td> <Td> when $a and $b are objects </Td> </Tr> <Tr> <Td> Python </Td> <Td> a is b </Td> <Td> a = = b </Td> <Td> </Td> </Tr> <Tr> <Td> Ruby </Td> <Td> a. equal? (b) </Td> <Td> a = = b </Td> <Td> </Td> </Tr>

Which of the following is a relational operator in php