Answer:
4. intangible assets.
Explanation:
Total assets are classified into current assets, fixed assets, and intangible assets.
Current assets comprise cash, stock, receivable account, etc.
Fixed assets include plant & machinery, property, facilities, furniture & equipment, etc.
And, the intangible assets are patents, copyrights, goodwill, and other intellectual properties plus they are not seen or even touched.
Whereas the fixed assets or other related synonymous are tangible in nature