Which scaling approach adds more nodes to distribute load and improve fault tolerance?

• A. Vertical scaling
• B. Horizontal scaling
• C. Diagonal scaling
• D. Circular scaling

Answer: (B)

Distributing load and boosting fault tolerance comes from adding more machines to the system and spreading work across them. This is horizontal scaling: you bring in additional nodes (servers) and use a load balancer to balance requests so no single machine bears all the load. If one node fails, others continue serving, improving resilience. Upgrading a single machine’s power is vertical scaling, which increases capacity of one node but doesn’t add redundancy. The other terms aren’t standard approaches for scaling in this context.