Which Time-Based Description of a Stage of Development in Pregnancy

Which time-based description of a stage of development in pregnancy is accurate?

A) Viability-22 to 37 weeks since the last menstrual period (assuming a fetal weight greater than 500 g)
B) Term-pregnancy from the beginning of week 38 of gestation to the end of week 42
C) Preterm-pregnancy from 20 to 28 weeks
D) Postdate-pregnancy that extends beyond 38 weeks