**Core Concept**
The spinal cord is a complex structure that requires precise surgical techniques for opening and exploration. The procedure is essential in various clinical scenarios, including spinal injuries, tumors, and infections. The correct approach involves identifying a specific location where the spinal cord can be safely opened without causing damage.

**Why the Correct Answer is Right**
The spinal cord is typically opened from the midline, specifically at the level of the posterior median sulcus. This approach allows for minimal damage to surrounding structures, including the anterior spinal artery and the spinal nerve roots. The posterior median sulcus is a natural cleavage plane that separates the two halves of the spinal cord, making it an ideal location for opening.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because opening the spinal cord from the lateral aspect would risk damaging the spinal nerve roots and the intervertebral discs.
**Option B:** This option is incorrect because opening the spinal cord from the anterior aspect would risk damaging the anterior spinal artery and the spinal cord itself.
**Option C:** This option is incorrect because opening the spinal cord from the posterior aspect without identifying the posterior median sulcus would risk causing significant damage to the spinal cord and surrounding structures.

**Clinical Pearl / High-Yield Fact**
During spinal cord surgery, it is essential to identify the posterior median sulcus to avoid damaging the spinal cord and surrounding structures. This can be achieved by using a combination of anatomical landmarks and intraoperative imaging techniques.

**Correct Answer:** C.