What is a main concern about psychology as a discipline? it will be used to manipulate people. it will use animals in research. it is a pseudoscience. it will treat humans inhumanely during research?

The main Concern is: It will be used to manipulate people.
Overall, Psychology studies the way human minds work. Which means that having a knowledge in psychology will make you much more likely to be able to influence other people's decision/behavior.
If this knowledge fall to the wrong hands, this could be used to manipulate people.