PCA (Prometheus Certified Associate) sample exam question with answer 562

Question:
Which of the following query functions returns a result of 1 if the specified time series does not exist?

1. absent
2. present
3. empty
4. missing

Answer:
A - is the correct answer. More at absent
B - is incorrect as this is not a PromQL function (though present_over_time is)
C, D - is incorrect as this is not a PromQL function