B. Golgi apparatus.
C. Intracellular vesicles.
D. Lumen of endoplasmic reticulum.
This structure is collagen triple helix structure.
Collagen is synthesized on ribosomes as pre-pro-collagen.
From there it enters the endoplasmic reticulum where the signal sequence is removed from the terminal end and glycosylation and hydroxylation of proline and lysine residues occur, resulting in the formation of procollagen.