A nurse is educating a newly pregnant client about the stages of pregnancy. The client asks, "Which weeks are included in the first trimester?" The nurse correctly responds with which of the following?

A. Weeks 25–36: This range falls within the third trimester of pregnancy. It includes the period of continued fetal growth and development, not the early developmental stages that define the first trimester. B. Weeks 1–12: The first trimester spans from conception through the 12th week of gestation. This period includes critical fetal organ development, hormonal shifts, and early pregnancy symptoms such as nausea and fatigue. C. Weeks 13–24: These weeks represent the second trimester, which is often marked by decreased early symptoms and increased fetal movement. It follows the completion of the first trimester at week 12. D. Weeks 37–40: This time frame represents the late third trimester, also referred to as term pregnancy. It involves preparation for labor and delivery, not early fetal development.