There are special rules in U.S. GAAP for software companies. For all otherproduct research and development, generally accepted accounting principles in the United States require firms to

	a.	expense all research and development costs in the period incurred
	b.	capitalize and amortize all research and development costs over a period no greater than 10 years
	c.	expense research costs and capitalize development costs to be amortized over the period they benefit
	d.	capitalize and amortize all research and development costs over a period no greater than 5 years
	e.	capitalize and amortize all research and development costs over the future expected benefit period