AZ-104 Deploy and Manage Azure Compute Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Place both VMs in an availability set.

  Why it's wrong here

  An availability set distributes VMs across fault domains and update domains within a single Azure datacenter. This protects against hardware failures (e.g., a failed rack) and planned maintenance reboots, but it cannot survive a full datacenter or zone outage because all VMs in the set share the same datacenter infrastructure. In other words, if that datacenter loses power or connectivity, both VMs in the availability set become unavailable simultaneously, so it does not meet the requirement for datacenter-failure resilience.

  When this WOULD be correct

  If the requirement is to protect against hardware failures within a single datacenter (e.g., rack failures) and planned maintenance, while ensuring VMs are placed close together for low latency, an availability set would be correct.

• ✓

  Deploy the VMs across availability zones.

  Why this is correct

  Availability zones place resources in physically separate datacenters within the same region. If one zone becomes unavailable, the other zone can continue serving traffic. That makes zones the correct choice when the requirement is resilience to a datacenter-scale outage. They provide stronger isolation than availability sets, which mainly protect against host and maintenance failures inside a single datacenter boundary.

• ✗

  Use a proximity placement group for both VMs.

  Why it's wrong here

  A proximity placement group intentionally co-locates VMs in the same Azure datacenter to minimize network latency, which directly increases the blast radius: if that datacenter experiences an outage, all VMs in the group go down together. It is a performance optimizer for tightly coupled workloads such as HPC or low-latency microservices, not a high-availability feature. In fact, using a proximity placement group for a stateless web app would make it less resilient than spreading VMs across availability zones.

  When this WOULD be correct

  For a latency-sensitive application (e.g., high-performance computing) where VMs must be physically close to minimize network latency, a proximity placement group is the correct choice, even if it means sacrificing fault tolerance.

• ✗

  Deploy both VMs in a single-zone virtual machine scale set.

  Why it's wrong here

  A single-zone virtual machine scale set places every VM instance in exactly one availability zone, so the entire workload shares that zone's fate. Although the scale set spreads instances across fault domains within the zone, a zone failure (e.g., fire, flood, or utility outage) takes down all instances at once. For zone-level resiliency, the scale set must instead be configured as a zonal or zone-redundant scale set spanning multiple availability zones, or you must deploy separate scale sets in different zones.

  When this WOULD be correct

  When the requirement is to scale out a stateless app within a single zone for low-latency inter-VM communication, and the question specifies protection only from planned host maintenance (not full datacenter outage).

Option-by-option analysis

Why each answer is right or wrong

Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The AZ-104 exam frequently reuses these exact scenarios with slightly different constraints.

Analysis generated from the official AZ-104blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”