Which of the following is an example of external factors leading to economic obsolescence?

The correct choice highlights a situation where external factors negatively influence the value of a property. Economic obsolescence, also known as external obsolescence, arises from outside the property itself and can significantly impact its market value.

Natural disasters impacting property serve as a significant example because they represent an uncontrollable external event that can lead to a permanent reduction in value. Events like floods, hurricanes, or earthquakes can cause extensive damage not only directly to the properties but also to the surrounding area, leading to a decline in desirability and market value.

In contrast, the other choices revolve around factors that are either more directly related to the property itself or are more subjective in nature. Outdated interior design reflects a property's internal condition or appeal, which is more of a functional obsolescence. Increased property taxes may impact affordability but are not directly tied to the economic viability or desirability of the property itself in terms of external factors. Lastly, a decline in property facilities, while potentially affecting value, pertains more to the specific property’s condition than to broader external economic impacts.

Thus, natural disasters illustrate a clear instance of external economic obsolescence because they are unforeseen external influences that diminish property value.