PCA (Prometheus Certified Associate) sample exam question with answer 342

Question:
What is the result of the following PromQL query: histogram_quantile(0.9, sum(rate(metric_name[5m])) by (le))

1. Calculates the 90th percentile of the metric values over a 5-minute period
2. Calculates the sum of metric values over a 5-minute period
3. Calculates the rate of increase of metric values over a 5-minute period
4. Calculates the average value of metric values over a 5-minute period

Answer:
A - correct answer. The histogram_quantile() function calculates the quantile of a histogram metric. The first argument is the quantile value, which is 0.9 in this case, indicating the 90th percentile. The second argument is the histogram metric