Final answer:
Preferred stock is sometimes treated like a debt security because preferred dividend payments are fixed in nature and preferred stock holders receive a residual value.
Step-by-step explanation:
Preferred stock is sometimes treated like a debt security because preferred dividend payments are similar to bond interest payments and are fixed in nature regardless of the firm's earnings (option B). Preferred stock holders receive a residual value and not a stated value, so they have a preference over common stockholders when it comes to receiving dividends (option D).