Mahmood works as a full stack web developer at Insignia Informatics. As one of the senior developers, Mahmood is often tasked with testing web applications built by his team. Often, he finds himself testing multiple web applications simultaneously over a short period. Mahmood uses a separate virtual machine to run each application in isolation. This often causes a resource crunch because each virtual machine uses large amounts of system resources, and Mahmood cannot be as productive as he wants to be$.$

What would you advise Mahmood?

a$.$ Avoid sandboxing in a testing environment

b$.$ Run these web applications in containers

c$.$ Increase the scalability of the system

d$.$ Use nested virtualization instead