Emily selects a new paint color for her bedroom. she notices a difference between sky blue and midnight blue. emily's ability to distinguish between these two colors can best be explained by the concept of
a) top-down processing.
b) selective attention.
c) sensory adaptation.
d) difference threshold.

d) difference threshold.

Explanation:

Difference Threshold:

The difference threshold which is also called noticeable difference is the least difference in stimulation that we can detect half of the time. When the difference is noticeable on the eye or can be felt we are able to detect it through threshold difference.

For example if you are carrying a 25 litre bucket of water with your hands and initially it has 10 litre of water inside as one keeps adding water on it you can feel the difference as it get heavier the ability to detect that change in how heavier the bucket is becoming is known as the threshold difference.

The ability for Emily to see and spot these differences between two colours which may look similar is through threshold difference to detect that least stimulation in differences.

it would be d). more resources must be obtained to attain that combination of goods and services