PCA (Prometheus Certified Associate) sample exam question with answer 295

Question:
What does the following config do?

scrape_configs:
  - job_name: "demo"
    metric_relabel_configs:
      - source_labels: [__name__]
        regex: docker_container_crash_total
        action: replace
        target_label: __name__
        replacement: docker_container_restart_total

1. Renames the metric docker_container_crash_total to docker_container_restart_total
2. Drops all targets with the docker_container_crash_total metric
3. Drops the docker_container_crash_total metric
4. Replaces all labels fro docker_container_crash_total

Answer:
A - correct answer