Which of the following variable declarations within a class is invalid in PHP?

Which is not a PHP magic constant?

Which will print out the PHP call stack?

What's the output?

Which is correct about Mysqli and PDO?

Correct way to send a SMTP (Simple Mail Transfer Protocol) email using PHP?

Which function opens an SQLite database and creates the database if it does not exist?

Which would be accepted as an argument parameter in the following function: function getEmotion(Emotion $emotion) { ... }

How do you retrieve the value of a variable called 'name' which has been passed from a submitted form?

What does MVC stand for?

HTML form input needs to be validated in order to avoid: