Which Statement Regarding the Condition Referred to as a Miscarriage

Which statement regarding the condition referred to as a miscarriage is most accurate?

A) A miscarriage is a natural pregnancy loss before labor begins.
B) It occurs in fewer than 5% of all clinically recognized pregnancies.
C) Careless maternal behavior,such as poor nutrition or excessive exercise,can be a factor in causing a miscarriage.
D) If a miscarriage occurs before the 12th week of pregnancy,then it may be observed only as moderate discomfort and blood loss.