**Core Concept**
Manual removal of placenta (MROP) is a procedure where the placenta is manually removed from the uterus after delivery. This procedure is usually performed when the placenta does not separate from the uterus on its own, a condition known as retained placenta. The underlying principle being tested here is the potential complications associated with MROP, which can arise due to the manipulation of the uterine cavity and its surrounding tissues.

**Why the Correct Answer is Right**
The correct answer is related to the potential complications of MROP, which include bleeding, infection, uterine atony, and damage to the uterine muscles or surrounding organs. The manipulation of the uterine cavity and its surrounding tissues during MROP can cause bleeding due to the disruption of blood vessels, leading to hemorrhage. Additionally, infection can occur if the placental tissue is not completely removed, allowing bacteria to enter the uterine cavity. Uterine atony, or the failure of the uterus to contract, can also occur due to the manipulation of the uterine muscles during MROP. Furthermore, damage to the uterine muscles or surrounding organs can occur, leading to long-term complications such as Asherman's syndrome or uterine rupture in subsequent pregnancies.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it is not a known complication of MROP. While uterine rupture can occur in subsequent pregnancies due to damage to the uterine muscles, it is not a direct complication of MROP.
* **Option B:** This option is incorrect because it is not a known complication of MROP. While infection can occur due to the manipulation of the uterine cavity, it is not as directly related to MROP as other complications such as bleeding or uterine atony.
* **Option C:** This option is incorrect because it is not a known complication of MROP. While uterine atony can occur due to the manipulation of the uterine muscles, it is not as directly related to MROP as other complications such as bleeding.

**Clinical Pearl / High-Yield Fact**
A key point to remember when considering MROP is that it should only be performed by an experienced healthcare provider in a controlled setting, as the potential complications can be severe and long-lasting. Additionally, MROP should only be performed when the placenta is not separating from the uterus on its own, as the manipulation of the uterine cavity and its surrounding tissues during MROP can cause significant complications.

**Correct Answer: C. Uterine atony**