At 34 weeks of gestation, a nurse reviews selected events from an antepartum nonstress test. Click the event that meets the gestational-age criteria for an acceleration.

C. C rises 20 beats/min for 24 seconds. It meets both criteria for this gestational age.

At 34 weeks, both a rise of at least 15 beats/min and a duration of at least 15 seconds are required. Compare height with baseline and measure onset to return, not the plateau alone. This item identifies one event; it does not classify the entire NST as reactive.

The observations are fictional teaching data. Apply the stated context; the selected feature does not by itself replace a complete bedside assessment.

Use gestational age, amplitude and duration together.

Use gestational age, amplitude and duration together.

A lasts long enough but rises only 12 beats/min. B rises 22 beats/min but returns in 12 seconds. D rises 12 beats/min for 12 seconds; the lower preterm criteria do not apply at 34 weeks.

• Gestational age and acceleration duration — Use gestational age, amplitude and duration together.
• Comparison with context — B has the largest rise but insufficient duration; D fits lower gestational-age thresholds.