Step 1: Understanding the Concept:
Fatty acid synthesis occurs in a specific cellular compartment.
This is different from fatty acid oxidation.
Step 2: Key Formula or Approach:
No specific formula.
Need to know the site of fatty acid synthesis.
Step 3: Detailed Explanation:
Fatty acid synthesis occurs in the mitochondria.
It is a cyclic process that builds fatty acids.
The nucleus is for DNA/RNA.
Ribosomes are for protein synthesis.
Endoplasmic reticulum is for protein processing.
Thus, fatty acid synthesis occurs in mitochondria.
Step 4: Final Answer:
Fatty acid synthesis occurs in mitochondria.
Hence, the correct option is (A).