Which of the following are types of "bad" potatoes?

The identification of "bad" potatoes revolves around certain characteristics that indicate they are not suitable for consumption. In this context, green potatoes are often harmful because they develop solanine, a toxic compound when exposed to light. Soft potatoes may indicate spoilage, as their texture can suggest decomposing or bacteria-related issues. Stale potatoes may have also lost their freshness and can develop an off flavor or undesirable texture.

Other options are comprised largely of healthy or commonly used types of potatoes. Options that list standard potato varieties or sizes do not inherently reflect any negative qualities. Thus, they do not represent "bad" potatoes as they tend to be safe and healthy for consumption. The key attribute of the selected answer is its focus on specific conditions that affect potatoes negatively, making them unsuitable for consumption, which is why it stands out as the correct choice.