**Core Concept**
The Nodal and Lefty 2 genes play a crucial role in the establishment of left-right asymmetry and embryonic development, particularly in the formation of the left-right axis. These genes are involved in the signaling pathways that regulate the asymmetric expression of genes and the subsequent morphogenesis of organs and tissues.

**Why the Correct Answer is Right**
The Nodal gene encodes a TGF-β family member that is essential for the establishment of left-right asymmetry in the embryo. It is activated in the left lateral plate mesoderm and induces the expression of Lefty 2, a negative feedback regulator that helps to maintain the left-sided expression of Nodal. This Nodal-Lefty 2 signaling pathway is critical for the proper development of the left-right axis and the subsequent formation of organs such as the heart, lungs, and liver.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because Nodal and Lefty 2 are not primarily involved in the regulation of cell cycle or apoptosis.
**Option B:** This option is incorrect because while Nodal and Lefty 2 are involved in embryonic development, they are not directly related to the development of the nervous system or neural crest.
**Option C:** This option is incorrect because Nodal and Lefty 2 are not primarily involved in the regulation of angiogenesis or blood vessel formation.

**Clinical Pearl / High-Yield Fact**
Mutations in the Nodal gene have been associated with left-right axis abnormalities and congenital heart defects, highlighting the importance of this gene in human development.

**Correct Answer: C. Left-right axis development and morphogenesis.**