What is the definition of full term infant

What is the definition of full term infant
A.baby born after 28~36 weeks' gestation
B.baby born after 37~41+6 weeks' gestation
C.baby born after 28~38 weeks' gestation
D.baby born after 26~36+6 weeks' gestation
正确答案：baby born after 37~41+6 weeks' gestation