This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to identify abnormal vaginal spotting between periods
Determine your normal menstrual period.
In order to distinguish between your normal menstrual period and abnormal spotting, you will need to be familiar with your normal cycle. This will help you to differentiate between what's normal and what's not.

Choices:
(a). A normal female menstrual cycle lasts for approximately 28 days, the first day of which is the first day of your monthly period. The bleeding usually lasts for 2 to 3 days but some women have it for as long as 6 days.;
(b). Your normal period typically lasts four to five days. In some cases, the abnormal period may stay on for more than one year.;
(c). Tracking your period in general can help you figure out what's normal and what's abnormal. The first time you get abnormal menstrual bleeding, which typically happens between late and mid-morning, it's the result of strong blockage of your blood vessels in your abdomen.;
(d). Your normal period is the first menstrual cycle, and it typically starts between 7 am to 12 pm. It can start around the same time everyday.;
The answer is:
(a).