**Core Concept**
Popcorn calcification is a characteristic radiological finding associated with certain types of breast lesions, particularly malignant ones. This calcification pattern is named due to its resemblance to the appearance of popcorn grains under mammography. It is indicative of a specific type of tumor behavior and growth pattern.

**Why the Correct Answer is Right**
Popcorn calcification is typically seen in mucinous carcinomas of the breast, also known as collagenous spherulosis. This type of cancer is characterized by the production of mucin, a type of glycoprotein, which accumulates in the tumor stroma and leads to the formation of characteristic calcifications. The calcifications in mucinous carcinomas appear as small, rounded, or oval-shaped densities that resemble popcorn grains due to their uniform size and distribution.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the calcification pattern described as "popcorn calcification" is not typically associated with fibroadenomas, which are benign breast tumors.
**Option B:** This option is incorrect because the calcification pattern described as "popcorn calcification" is not typically associated with ductal carcinoma in situ (DCIS), which is a type of non-invasive breast cancer.
**Option C:** This option is incorrect because the calcification pattern described as "popcorn calcification" is not typically associated with phyllodes tumors, which are rare breast tumors that can be benign, borderline, or malignant.

**Clinical Pearl / High-Yield Fact**
Mucinous carcinomas of the breast are often associated with a favorable prognosis and a lower risk of lymph node metastasis compared to other types of breast cancer. However, they can still exhibit aggressive behavior and require prompt diagnosis and treatment.

**Correct Answer:** C.