Final answer:
The least expensive and least invasive method of breast biopsy is Fine Needle Aspiration Biopsy (FNAB). FNAB involves using a thin needle to extract cells or fluid from a breast mass.
Step-by-step explanation:
The least expensive and least invasive method of breast biopsy is Fine Needle Aspiration Biopsy (FNAB). FNAB involves using a thin needle to extract cells or fluid from a breast mass. It is typically performed under local anesthesia and does not require a surgical incision.
Other breast biopsy methods such as core biopsy, stereotactic breast biopsy, and open surgical biopsy are generally more invasive and may require a larger incision or removal of a tissue sample.