How can you access the value of a form field named "username" submitted via the POST method in PHP?

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

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 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 redirect the user to another page?

A). redirect()

B). header()

C). forward()

D). location()

What is the purpose of the trim() function in PHP?

A). To remove whitespace from the beginning and end of a string.

B). To truncate a string to a specified length.

C). To convert a string to lowercase.

D). To convert a string to uppercase.

What function is used to validate email addresses in PHP?

A). validate_email()

B). filter_var()

C). check_email()

D). email_validate()

What type of attribute is used in an HTML form to specify where to send the form data?

A). method

B). action

C). type

D). name

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 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()

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