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Which of the following statements correctly explains the use of instanceof and type hinting?

Each correct answer represents a complete solution. Choose three.

The instanceof operator lets a programmer inspect all of the ancestor classes of the object, as well as any interfaces.

The instanceof operator can be used to check if the variables are the member of an abstract class.

The instanceof operator can be used to check if the variables are an instance of a particular class.

Type hinting is a feature due to which functions can specify what type of parameters must be provided to the functions.

Explanation: Answer options A, D, and C are correct.

The instanceof operator lets a programmer inspect all of the ancestor classes of the object, as well as any interfaces. It can also be used to decide whether or not an object of a class is inheriting property from another class. The following example explains the use of the instanceof operator:

<?php
 class A
 { var $variable;
 function display()
 {
 echo "I am inside the class.";
 }
 }
$obj=new A;
var_dump($obj instanceof A);

Output: bool(true)
?>

In PHP 5, type hinting is a feature due to which functions can specify what type of parameters must be provided to the functions. If that parameter is not of the correct type, the PHP script will give an error. Type hinting is not supported for strings and integers. Type hinting can also help in code completion in an IDE.

Answer option B is incorrect. The instanceof operator cannot be used to check if the variables are the member of an abstract class.

Reference: http://php.net/manual/en/language.operators.type.php