The correct answer is (c), Intangible Real Account.
A patent is an intangible asset that gives its owner the exclusive right to make, use, or sell an invention for a limited period of time. Patents are considered real accounts because they represent a valuable asset that can be used to generate future cash flows. However, they are intangible because they do not have a physical form.
Nominal accounts, on the other hand, are used to track expenses and revenues. They are not considered assets or liabilities, and they are not carried forward to the next accounting period.
Personal accounts are used to track the financial transactions of individuals or businesses. They are not considered assets or liabilities, and they are not carried forward to the next accounting period.
Tangible assets are physical objects that have value. They include things like land, buildings, equipment, and inventory.
Intangible assets are non-physical assets that have value. They include things like patents, trademarks, copyrights, and goodwill.