Final answer:
Ultrasound is the imaging modality of choice for TOA. It can show a complex mass filled with fluid in the pelvis or abdomen.
Step-by-step explanation:
The imaging modality of choice for TOA (Tubo-Ovarian Abscess) is ultrasound (c).
An ultrasound can produce images of the pelvis and abdomen and can show a complex mass filled with fluid, which is characteristic of a TOA.
Ultrasound technology is non-invasive and does not use electromagnetic radiation, making it a preferred imaging modality for TOA.