What is an example of a "condolence"?

A condolence refers to an expression of sympathy, especially offered to someone who is experiencing grief or mourning the loss of a loved one. When someone sends a condolence message, it serves to comfort the bereaved and convey feelings of sorrow for their loss. This aligns directly with the definition of condolence, making it the most suitable choice in this context.

The other options do not reflect the meaning of condolence. A greeting card could be used for various purposes, not exclusively for expressing sympathy. An expression of joy is contrary to the sentiments associated with condolence, which focuses on sorrow and support. A business proposal is unrelated as it pertains to formal offers in a commercial context, lacking any emotional or sympathetic connotation. Therefore, a sympathy message is the clear representation of what a condolence truly is.