What is the purpose of the htmlspecialchars() function in PHP?
A). To convert HTML entities to their corresponding characters.
B). To remove HTML tags from a string.
C). To encode special characters in HTML format.
D). To decode special characters in HTML format.
Which PHP superglobal array is used to retrieve form data sent with the POST method?
A). $_POST
B). $_GET
C). $_REQUEST
D). $_SERVER
How can you check if a checkbox is checked in PHP when submitted via a form?
A). isset($_POST['checkbox'])
B). $_POST['checkbox'] == 'checked'
C). $_POST['checkbox'] === 'checked'
D). empty($_POST['checkbox'])
Which attribute of the HTML <form> element specifies the HTTP method to be used when submitting the form data?
A). method
B). action
C). type
D). enctype
Which PHP function is used to sanitize user input to prevent SQL injection attacks?
A). strip_tags()
B). htmlspecialchars()
C). mysql_real_escape_string()
D). trim()
How can you access the value of a form field named 'username' submitted via the POST method in PHP?
A). $_GET['username']
B). $_POST['username']
C). $_REQUEST['username']
D). $_SERVER['username']
What function is used to check if a file upload operation was successful in PHP?
A). file_exists()
B). is_uploaded_file()
C). move_uploaded_file()
D). file_upload_successful()
What is the purpose of the isset() function in PHP when handling form submissions?
A). To check if a variable is empty
B). To check if a variable is set and is not NULL
C). To check if a variable is numeric
D). To convert a variable to a string
What function is used to validate email addresses in PHP?
A). validate_email()
B). filter_var()
C). check_email()
D). email_validate()
Which attribute of the HTML <form> element specifies the HTTP method to be used when submitting the form data?
A). method
B). action
C). type
D). enctype