4.
Given the following code, what will be the output?
let string = "Hello, world!";
console.log(string.includes("world"));
Syntax Error
False
True
Undefined
Correct: C
In JavaScript, the includes() method can be used to check if a string contains a specified string. It returns a boolean value "true" if the string contains the specified string, and "false" if it does not. In the given code, Hello, world! does contain "world", so the output of the code will be True.