One company incurred $$2$ million in research and development costs. What is the accounting treatment of these costs?

a$.$ They are accounted for as an expense as incurred.

b$.$ They are accounted for as an intangible asset with a limited life

c$.$ They are accounted for as an indefinite$-$lived intangible asset.

d$.$ If the company receives a patent as a result of these costs, the $$2$ million is added to the cost of the patent.