Answer :
The correct answer is:
d. Endoplasmic Reticulum
Explanation:
1. The endoplasmic reticulum (ER) is a cell organelle where proteins, lipids, and carbohydrates are made.
2. It consists of two main parts: the rough endoplasmic reticulum (RER) and the smooth endoplasmic reticulum (SER).
3. The RER is studded with ribosomes on its surface and is responsible for protein synthesis.
4. The SER does not have ribosomes on its surface and is involved in lipid and carbohydrate metabolism.