PCA (Prometheus Certified Associate) sample exam question with answer 115

Question:
An engineer forgot to address an alert, based off the alertmanager config below, how long will they need to wait to see the alert again?

route:
  receiver: pager
  group_by: [alertname]
  group_wait: 10s
  repeat_interval: 4h
  group_interval: 5m
  routes:
  - match:
      team: api
    receiver: api-pager
  - match:
      team: frontend
    receiver: frontend-pager

1. 5m
2. 4h
3. 15s
4. 10s

Answer:
B