Consider the following statements regarding endoplasmic reticulum and choose the correct answer:
1. The endoplasmic reticulum appears to have a combination of triple-layered and micellar structures
2. Geometric symmetry is lacking in ER membranes, which are asymmetrical
3. The rough endoplasmic reticulum (RER) is the site of secretion of secretory proteins
4. The smooth endoplasmic reticulum (SER) membranes appear to be involved in the formation of lipoprotein complexes

A. Only 1, 2 and 3 are correct

B. Only 1, 2 and 4 are correct

C. Only 2, 3 and 4 are correct

D. Only 1, 3 and 4 are correct

Answer: Option D