## Core Concept
Placenta previa is a condition in pregnancy characterized by the placenta partially or wholly covering the internal cervical os. This condition is a major cause of antepartum hemorrhage. Understanding the types, causes, and clinical presentation of placenta previa is crucial for managing pregnant women.

## Why the Correct Answer is Right
To answer this question accurately, one needs to assess each option given about placenta previa and identify the statement that does not hold true. Since the specific details of options A, B, C, and D are not provided, a general approach to evaluating statements about placenta previa is necessary. Generally, true statements about placenta previa might include its classification (e.g., complete, partial, marginal), risk factors (e.g., multiparity, advanced maternal age, previous uterine surgery), and clinical features (e.g., painless vaginal bleeding).

## Why Each Wrong Option is Incorrect
Without specific details on the options, a general explanation applies:
- **Option A:** If this option describes a known risk factor, classification, or clinical feature of placenta previa, it would be considered true unless it inaccurately represents current medical understanding.
- **Option B:** Similarly, if this option misrepresents a characteristic of placenta previa, it would be incorrect based on established medical knowledge.
- **Option C:** This option would be incorrect if it suggests a feature or consequence not associated with placenta previa.
- **Option D:** As the correct answer is associated with this option, any statement here that contradicts established facts about placenta previa would make it the correct choice.

## Clinical Pearl / High-Yield Fact
A key point to remember is that placenta previa is often associated with **painless vaginal bleeding** in the second or third trimester. Risk factors include a history of uterine surgery (like cesarean sections), multiparity, and placenta location abnormalities. A critical clinical correlation is that ultrasound is used for diagnosis, showing the placenta's relationship to the internal os.

## Correct Answer: D.