**Core Concept**
Double aoa, also known as double aortic arch, is a rare congenital anomaly of the aortic arch. It is characterized by the presence of two aortic arches that encircle the trachea and esophagus, rather than the usual single aortic arch.

**Why the Correct Answer is Right**
The double aoa develops from the sixth aortic arches, which are paired structures that arise from the aortic sac. Normally, the left sixth aortic arch develops into the aortic arch, while the right sixth aortic arch atrophies. However, in the case of double aoa, both left and right sixth aortic arches develop and persist, forming two separate aortic arches. This anomaly can lead to compression of the trachea and esophagus, causing respiratory and gastrointestinal symptoms.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the development of double aoa.
* **Option B:** This option is incorrect because the double aoa does not develop from the dorsal aorta.
* **Option C:** This option is incorrect because the double aoa does not develop from the outflow tracts of the heart.

**Clinical Pearl / High-Yield Fact**
The double aoa is a rare congenital anomaly that can be associated with other cardiac and non-cardiac anomalies. It is essential to suspect this condition in patients with symptoms of tracheal or esophageal compression, particularly those with a history of congenital heart disease.

**Correct Answer: D. The sixth aortic arches.**