Final answer:
Reaction range describes the extent to which traits, abilities, or IQ scores can change due to environmental influences, considering an individual's genetic potential. The correct option is D.
Step-by-step explanation:
The extent to which traits, abilities, or IQ scores may increase or decrease as a result of environmental factors is called reaction range. This concept encompasses the idea that while our genetic makeup sets certain boundaries, the environment in which we are raised helps determine where within those limits we actually fall.
If a child with average genetic potential is raised in a highly stimulating environment, they are likely to reach a higher level of intellectual potential than they would in a less stimulating environment.
Conversely, even a child with a high genetic potential may not reach their full intellectual capacity if raised in an environment lacking stimulation. This interplay of genetics and environment in shaping intelligence is an example of the nature-nurture debate in psychology. The correct option is D.