Interfaces can extend only one interface

Interfaces can extend more than one interface

Interfaces can inherit a method from different interfaces

Interfaces can redeclare inherited methods

implement Traversable

is an instance of ArrayObject

implements ArrayAccess

None of the above

Using the headers_sent() function.

Using the output_start() function.

Using the ob_start() function.

Cannot be determined

SimpleXML allows removal of attributes.

SimpleXML allows addition of new attributes.

SimpleXML allows removal of nodes.

SimpleXML allows addition of new nodes.

None of the above

Only methods can have type hints

Typehints can be optional

Typehints can be references

$xml- > bar[ ' foo ' ]

$xml- > bar- > foo

$xml[ ' document ' ][ ' bar ' ][ ' foo ' ]

$xml- > document- > bar- > foo

$xml- > getElementByName( ' foo ' );

addslashes()

htmlentities()

htmlspecialchars()

strip_tags()

quotemeta()

(int) ' t ' ;

ord( ' t ' );

to_ascii( ' t ' );

chr( ' t ' );

$_GET[ ' ALL ' ]

$_SERVER[ ' QUERY ' ]

$_SERVER[ ' QUERY_STRING ' ]

$_ENV[ ' QUERY ' ]

$QUERY_STRING

file_put_contents( " file " , " data " , " a " );

file_put_contents( " file " , " a " , " data " );

file_put_contents( " file " , " data " , FILE_APPEND);

file_put_contents( " file " , " a " , NULL, FILE_APPEND);