What level of redundancy does a Tier IV data center provide?

A Tier IV data center offers the highest level of redundancy and fault tolerance, which is why multiple active paths with fault tolerance is the correct answer. This means that if one path fails, the system can continue to operate without interruption due to the presence of alternative paths that can take over seamlessly.

Tier IV facilities are designed to ensure that any component, whether it's electrical or mechanical, has redundancy built-in. This allows the data center to be resilient against multiple failures, maintaining service availability and high levels of uptime. The fault tolerance of a Tier IV data center is crucial for organizations that require uninterrupted access to their critical systems and data, such as those in the finance, healthcare, and telecommunications sectors.

Given that the other options describe lower levels of redundancy, they do not align with the specifications and standards of a Tier IV data center.