Step 1: Understanding glycolysis.
Glycolysis is the breakdown of glucose into pyruvate and occurs in the cytoplasm of the cell. It is the first step in cellular respiration.
Step 2: Analyzing the options.
(A) Golgi body: Incorrect — The Golgi body is involved in modifying and packaging proteins, not glycolysis.
(B) mitochondria: Incorrect — Glycolysis takes place in the cytoplasm, not the mitochondria.
(C) chloroplast: Incorrect — Chloroplasts are involved in photosynthesis, not glycolysis.
(D) cytoplasm: Correct — Glycolysis occurs in the cytoplasm.
Step 3: Conclusion.
The correct answer is (D) cytoplasm, as glycolysis occurs in the cytoplasm of the cell.