Final answer:
The oldest and largest radiologic science professional organization is the American Society of Radiologic Technologists (ASRT) that was founded in 1920.
Step-by-step explanation:
The world's oldest and largest radiologic science professional organization is the American Society of Radiologic Technologists (ASRT). ASRT was founded in 1920 and represents the interests of more than 150,000 medical imaging and radiation therapy professionals.
ASRT provides resources, education, and advocacy for members in the field of radiologic science. They offer continuing education programs, research grants, and publications to keep professionals up to date with the latest advancements in the field.
The organization plays a crucial role in promoting the highest standards of patient care and safety in radiologic science.