Final answer:
Ductography is the technique whereby contrast is injected into the ducts to check for an abnormality.
Step-by-step explanation:
The technique whereby contrast is injected into the ducts to check for an abnormality is called ductography. Ductography is a type of medical imaging technique used to visualize the milk ducts in the breast. It involves injecting a contrast agent into the ducts and then taking X-ray images to detect any abnormalities or blockages.