What is the purpose of the isset() function in PHP when handling form submissions?

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

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']

Which function is used to check if a variable is an array in PHP?

A). is_array()

B). check_array()

C). array_check()

D). isArray()

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 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'])

How can you prevent SQL injection attacks in PHP?

A). Use prepared statements with parameterized queries.

B). Escape user input using the htmlspecialchars() function.

C). Sanitize user input using the filter_var() function.

D). Validate user input using regular expressions.

Which PHP superglobal array is used to retrieve form data sent with the POST method?

A). $_POST

B). $_GET

C). $_REQUEST

D). $_SERVER

What function is used to validate email addresses in PHP?

A). validate_email()

B). filter_var()

C). check_email()

D). email_validate()

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 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