Which of the following is considered an improvement to real property?

An improvement to real property is defined as any addition or change to the property that enhances its value or utility, making it more functional or aesthetically pleasing. In this context, a garden fence qualifies as an improvement because it is a permanent structure that enhances the overall property. It defines the boundaries of the property, adds privacy, and can contribute to the property's curb appeal and value.

The other options do not fit this definition of an improvement. For instance, a tenant's refrigerator is considered personal property rather than a fixture of the real estate, as it is not permanently affixed to the property. Similarly, furniture is also classified as personal property and does not enhance the property itself. A mobile home, unless permanently affixed to a foundation, is often seen as personal property and not an improvement to the real estate. Therefore, the garden fence stands out as the correct answer in terms of it contributing to the enhancement of real property value.