Sabrina is a 25 year old female who presents to your office…

Sabrina is a 25 year old female who presents to your office for her yearly physical exam and reports she recently felt a “small lump” in her left breast. Upon examination you note a single small lump that is approximately 1 cm in size to her left breast. the lump is round and almost disc-like. It is non tender, very mobile, and there are no other abnormalities notes to her breast or surrounding structure. You know this lump warrants further investigation, but the most likely diagnosis is: