The correct answer is that segmentation reduces the attack surface within the network. By dividing the network into smaller segments, each with its own security controls and policies, the potential for an incident in one segment to affect others is limited, thus reducing the overall attack surface. Implementing VLANs or enforcing subnetting are common methods of achieving segmentation. Incorrect answers such as preventing data leakage and enhancing data encryption might seem plausible as they also relate to network security, but they are not the primary security benefits of segmentation. While increasing scalability is important, it is not directly a security benefit but rather an architectural one.