Currency risk is based on what assumption? A$.$ The value of one dollar today is greater than the value of one dollar to be received one year from now. B$.$ Changing product lines by reacting to every current trend may alienate the customer base. C$.$ Firms that do not continuously innovate will lose market share. D$.$ Values of foreign currencies continually rise and fall in most countries. E$.$ The U$.$S$.$ stock market fluctuates daily.