Choice B reason: Early decelerations are gradual decreases in fetal heart rate that mirror uterine contractions. They are caused by fetal head compression and are considered benign, not associated with fetal distress or cord problems. They are expected during labor and do not indicate pathology.

Choice C reason: Late decelerations occur after the peak of a contraction and are associated with uteroplacental insufficiency, not cord compression. They indicate impaired oxygen exchange between mother and fetus, often due to maternal hypotension, uterine hyperstimulation, or placental dysfunction. While serious, they are not linked to cord problems.

Choice D reason: Accelerations are transient increases in fetal heart rate and are considered reassuring signs of fetal well-being. They indicate adequate oxygenation and intact neurologic response. Accelerations are not associated with cord compression or fetal compromise.