The answer may be D, discrimination
Answer:cone of vision
Explanation:
The cone of vision is defined as you visual region which is drawn to show how your normal vision looks like without your peripheral vision. In a simple term it means it shown your angle of sight in drawing .
Answer:Internal Invalidity
Explanation:
Internal Invalidity means something else produces the outcome that is observed in a research and is a result of the conclusion made from that experiment , something else other than the actual stimulus that was meant to produce those results in an experiment. This means these result may not be a true representation of the research outcome because something else has intervened and had it effect on the participants. Dependent variable are affected by something else outside of the experimental stimulus.
"participants get more benefit from the human contact of a research " this is something else other than the clinical treatment.