Final answer:
Implementing user login and signup with PHP and OOP involves both PHP scripting and Object-Oriented Programming.
Step-by-step explanation:
The answer to this question is b) Both PHP scripting and Object-Oriented Programming (OOP).
Implementing user login and signup with PHP and OOP requires using PHP scripting to handle the server-side logic and Object-Oriented Programming concepts to design and structure the code.
For example, you can use PHP scripting to interact with a database to store user information and validate login credentials, while OOP can be used to create user classes with properties and methods for efficient code organization and reusability.