Which term refers to the action or process of adapting to new conditions?

The term that refers to the action or process of adapting to new conditions is "adaptation." It encompasses the various changes that organisms or systems undergo to better fit their environments. Adaptation can occur at multiple levels, from physiological and behavioral changes in individuals in response to changing environmental factors to genetic changes in populations over generations.

Acclimatization, while closely related, specifically refers to the short-term physiological adjustments an individual might make in response to environmental changes, such as temperature shifts or altitude changes. Modification suggests a broader alteration but does not specifically imply the process of adapting to environmental conditions. Transformation tends to indicate a more fundamental change rather than the specific process of adapting to new conditions.

Thus, "adaptation" most accurately captures the ongoing process of adjustment necessary for survival and functioning in a changing environment.