PCA (Prometheus Certified Associate) sample exam question with answer 110

Question:
Which of the following is NOT a metric generated by Prometheus automatically when performing a scrape?

1. scrape_payload_bytes
2. scrape_samples_scraped
3. up
4. scrape_duration_second

Answer:
A - automaticallygenerated labels and time series
B, C, D - this are the metrics generated by Prometheus when it performs a scrape