Healthy forests are more _____ to natural forest pests.

Healthy forests are more resistant to natural forest pests because they possess a diverse array of tree species, robust soil health, and a balanced ecosystem that includes various predators and beneficial organisms. This biodiversity helps to prevent pests from spreading easily and mitigates their effects. A forest with strong, healthy trees is better able to defend itself against infestations due to its inherent physical and biochemical defenses, such as thicker bark, resin production, and other natural resistances. These attributes enable trees to withstand pest attacks and recover from damage more effectively than weakened forests.

In contrast, adaptability refers to the capability of a forest to change in response to environmental influences, which doesn't specifically equate to resistance against pests. Vulnerability implies susceptibility, meaning that a healthy forest would actually be less vulnerable to pests. The idea of attractiveness suggests that healthy forests may draw more pests, but this is not a direct measure of the forest’s ability to resist them. Hence, the most accurate term to describe the relationship between healthy forests and their interaction with pests is resistance, highlighting their ability to fend off infestations.