Callable preferred stock is most likely to be called when interest rates are falling, which makes choice C correct. The “call” feature gives the issuer the right (but not the obligation) to redeem the preferred stock at a stated call price after a certain date. Issuers tend to exercise call provisions when it becomes economically beneficial—most commonly when they can refinance or replace the outstanding security with a new issue that has a lower dividend rate (lower cost of capital).
When interest rates fall, newly issued preferred stock (and other income-focused securities) can often be sold with lower dividend yields because investors will accept lower yields in a lower-rate environment. If the issuer has older preferred shares outstanding that pay a relatively high dividend, the issuer may choose to call those shares and issue new preferred at a lower rate, reducing financing costs. This is similar to why callable bonds are often redeemed when rates decline: the issuer can refinance at cheaper levels.
If interest rates are rising (choice B), calling an existing higher-dividend preferred would usually be disadvantageous because a replacement issue would likely require an even higher dividend to attract investors, increasing costs. If rates are stable or merely fluctuating (choices A and D), there is no consistent incentive that makes calling “most likely.” The strongest, most tested driver is a declining rate environment.
On the SIE, this question targets call risk and reinvestment risk for investors: when a security is called, investors receive principal back and may be forced to reinvest at lower yields. Understanding the issuer’s incentive is key: issuers call when it benefits them, typically when rates fall.