When we're doing scientific research, we should definitely be avoiding any sources which aren't scientific by nature. This means we should avoid sources which haven't been peer reviewed by fellow authors of a similar field. With this, we avoid using literature of questionable quality.
The correct answer is option 3, that is, lysosome.
The lysosomes comprise hydrolytic enzymes essential for intracellular digestion. They are commonly found in the cells of animals but are rare in plant cells. In the plant cells, the hydrolytic enzymes are most often found in the vacuoles.
The other mentioned components like cell wall are exclusively found in plant cells, not in animal cells, vacuole is found in both plant and animal cells, it is bigger in plant cells in comparison to animal cells, and the mitochondria are witnessed in both plant and animal cells.