{
  "id": "labels-selectors-mcq",
  "title": "Labels and Selectors",
  "category": "Core Concepts",
  "difficulty": "Easy",
  "type": "mcq",
  "weight": 3,
  "description": "## Labels and Selectors\n\nYou run the following command:\n\n```bash\nkubectl get pods -l env=prod,tier=frontend\n```\n\nWhat does this command return?",
  "options": [
    {
      "id": "a",
      "text": "Pods that have BOTH `env=prod` AND `tier=frontend` labels"
    },
    {
      "id": "b",
      "text": "Pods that have either `env=prod` OR `tier=frontend` labels"
    },
    {
      "id": "c",
      "text": "Pods that do NOT have `env=prod` or `tier=frontend` labels"
    },
    {
      "id": "d",
      "text": "All pods, sorted by the `env` and `tier` label values"
    }
  ],
  "correct_option": "a",
  "explanation": "When you specify multiple label selector expressions separated by commas, Kubernetes applies a logical **AND** — all conditions must be true. Only pods that have both `env=prod` **and** `tier=frontend` are returned. Use `-l 'env in (prod,staging)'` for OR-style matching.",
  "hints": [
    {
      "title": "How comma-separated selectors work",
      "body": "The `-l` flag accepts a comma-separated list of `key=value` expressions. Multiple expressions are ANDed together — all must match for a pod to be included in the result.",
      "command": "kubectl get pods -l env=prod,tier=frontend"
    }
  ],
  "setup_commands": [],
  "default_namespace": "default",
  "teardown_commands": []
}