Which of the following can indicate potential mold presence?

The identification of potential mold presence in a property often relies on observable indicators. Visible stains on walls are a significant sign; these discolorations typically result from moisture issues, which can facilitate mold growth. When water leaks occur or when there’s high humidity, it can lead to conditions that promote mold development, making visible stains a key indicator for inspectors.

In addition to stains, unusual odors are also a strong indicator of mold presence. Mold often produces a musty smell, which can serve as a warning sign that mold colonies may exist, even if they are not immediately visible. Thus, both visible stains and unusual odors point towards moisture problems that create a favorable environment for mold.

By acknowledging both visible stains on walls and unusual odors, the correct choice encompasses the various ways mold issues can manifest, making "Both A and B" the most comprehensive answer.