Final answer:
Ultrasound is the safest and preferred imaging study for diagnosing appendicitis during pregnancy due to its use of high-frequency sound waves without radiation.
Step-by-step explanation:
The imaging study that is best for diagnosing appendicitis in pregnancy is an ultrasound. This imaging technique is considered the safest for pregnant patients because it uses high-frequency sound waves without radiation. The ultrasound can produce real-time images for the diagnosis of various conditions, including appendicitis, and it is particularly advantageous during pregnancy when minimizing exposure to ionizing radiation is paramount. Options like CT scans and PET scans involve ionizing radiation and are typically avoided unless absolutely necessary. Ultrasonography's non-invasive nature and lack of radiation make it the preferred choice for examining the appendix during pregnancy.