Clustering is a technique, which includes the Microsoft Windows and the coordination with an individual multi-PC's, that is mostly connected to the local area network, as a single platform.
It is cheaper than one device.
It enables you to greater machine performance and increases usability and reliability, that's why the answer to this question is "Clustering".
Option 2 is correct because most of the components used in laptop is far different from Desktops. They are not able to fix in desktops. They are designed specially for laptops.