Final answer:
A chloroplast transforms light energy into chemical energy through photosynthesis, while a vacuole stores water along with other substances, helping in maintaining cell structure and storage in plant cells.
Step-by-step explanation:
Chloroplasts and vacuoles are both enclosed by membranes and considered organelles within plant cells, serving different functions. The correct answer to how a chloroplast is different from a vacuole is: d) A chloroplast transforms light energy, and a vacuole stores water and other substances. Chloroplasts perform photosynthesis, a process where carbon dioxide, water, and light energy are transformed into glucose and molecular oxygen. This process occurs within the thylakoids and stroma of the chloroplast. On the other hand, vacuoles primarily serve as storage compartments within plant cells, which can store water, nutrients, and waste products. They are particularly large in plant cells, where they also help in maintaining turgor pressure which is vital for plant structure and growth.