Final answer:
Investments should be classified as long-term assets when they are expected to be held for a significant period of time, typically exceeding one year.
Step-by-step explanation:
Investments should be classified as long-term assets under the condition that they are expected to be held for a significant period of time, typically exceeding one year. Long-term assets are those that are not easily converted into cash and are intended for use or benefit of the organization over a longer period. Examples of long-term assets include real estate, machinery, and research and development projects.