**Core Concept**
A complete hydatidiform mole is a type of gestational trophoblastic disease characterized by an abnormal growth of trophoblastic cells in the uterus, leading to the formation of a non-viable fetus. It is a rare condition that occurs when there is an abnormal fertilization of an egg, resulting in a diploid genome composed entirely of paternal DNA.

**Why the Correct Answer is Right**
A complete hydatidiform mole is typically of paternal origin, resulting from the fertilization of an empty egg by one or more sperm. This leads to a diploid genome with 46 chromosomes, all of which are paternal in origin. The presence of a complete hydatidiform mole is often associated with an enlarged uterus, vaginal bleeding, and elevated levels of human chorionic gonadotropin (hCG). The condition is more common in developing countries, where access to prenatal care and screening is limited.

**Why Each Wrong Option is Incorrect**
* **Option A:** This is incorrect because the chromosome pattern of a complete hydatidiform mole is typically 46,XX, but this is due to the fertilization of an egg by two sperm, resulting in two sets of paternal chromosomes.
* **Option B:** This is incorrect because a complete hydatidiform mole is typically of paternal origin, resulting from the fertilization of an empty egg by one or more sperm.
* **Option C:** This is incorrect because while an enlarged uterus may be associated with a complete hydatidiform mole, an enlarged ovarian cyst is not a characteristic feature of this condition.
* **Option D:** This is incorrect because complete hydatidiform moles are actually more common in developing countries, where access to prenatal care and screening is limited.
* **Option E:** This is incorrect because while preeclampsia can occur in association with a complete hydatidiform mole, it is not a characteristic feature of this condition.

**Clinical Pearl / High-Yield Fact**
A complete hydatidiform mole is a rare but serious condition that requires prompt recognition and treatment to prevent complications. It is essential for clinicians to be aware of the characteristic features of this condition, including an enlarged uterus, vaginal bleeding, and elevated levels of hCG.

**Correct Answer:** b. It is of maternal origin