**Core Concept**
The sacrotuberous ligament is a significant ligament in the posterior pelvis, connecting the sacrum to the tuberosity of the ischium. It plays a crucial role in stabilizing the pelvis and transmits forces from the sacrum to the ischium.

**Why the Correct Answer is Right**
The sacrotuberous ligament is not pierced by any major nerves or vessels. However, it is worth noting that the sacrotuberous ligament does transmit the short posterior sacroiliac ligament, which is an intraligamentous structure. Moreover, the ligament has a close relationship with the posterior sacral foramina and the sacral hiatus. The ligament also has a fibrous connection with the sacrotuberous ligament's fellow posterior ligament, the sacrospinous ligament.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as the sacrotuberous ligament does not contain any significant blood vessels or nerves. However, the ligament does have some vascular supply from the posterior branches of the internal iliac artery.
**Option B:** This option is incorrect as the sacrotuberous ligament is pierced by the short posterior sacroiliac ligament, which is an intraligamentous structure.
**Option C:** This option is incorrect as the sacrotuberous ligament does not have a significant relationship with the sciatic nerve, but it is in close proximity to the posterior branches of the internal iliac artery and the sciatic nerve.

**Clinical Pearl / High-Yield Fact**
Remember that the sacrotuberous ligament has a close relationship with the posterior sacral foramina and the sacral hiatus, making it an important structure to consider in posterior pelvic surgeries.

**Correct Answer: D. Sciatic nerve**