**Core Concept**
A cervical fibroid, also known as a pedunculated fibroid, is a type of leiomyoma that projects from the cervix into the vagina. Its distinctive appearance is due to the stalk-like pedicle that attaches it to the cervix, resembling a lantern on top of St Paul's Cathedral.

**Why the Correct Answer is Right**
The "lantern on top of St Paul's Cathedral" description refers to the characteristic appearance of a cervical fibroid, where the pedunculated fibroid projects from the cervix, resembling a lantern attached to a stalk. This type of fibroid is specifically located on the cervix, which is the lower part of the uterus. The pedicle is the stalk-like structure that attaches the fibroid to the cervix, distinguishing it from other types of fibroids. In this case, the fibroid is not submucosal (embedded in the uterine wall), subserosal (located on the outer surface of the uterus), or interstitial (located within the uterine wall).

**Why Each Wrong Option is Incorrect**
**Option A:** A submucosal fibroid is embedded in the uterine wall, not projecting from the cervix like a pedunculated fibroid.
**Option B:** A subserosal fibroid is located on the outer surface of the uterus, not specifically on the cervix.
**Option D:** An interstitial fibroid is located within the uterine wall, not projecting from the cervix.

**Clinical Pearl / High-Yield Fact**
When examining a patient with suspected cervical fibroids, it's essential to note the location and appearance of the fibroid, as well as any symptoms such as pelvic pressure or pain. A cervical fibroid can be a diagnostic challenge, but recognizing its characteristic appearance can aid in accurate diagnosis.

**✓ Correct Answer: C. Cervical fibroid**