The __ function is used to encode a URL.
*Matching is case-insensitive.
urlencode
Correct:
urlencode
Explanation: The urlencode() function is used to encode a URL. It returns a string in which all non-alphanumeric characters are replaced with a percent (%) sign followed by two hex digits. However, it does not encode - (dash) and _ (hyphen) characters. It encodes spaces as plus (+) signs.