Final answer:
As different studies suggest that 28 percent of U.S. adults may be affected by anxiety disorders and 21 percent by mood disorders over their lifetimes, it is estimated that about 50 percent of adults in the U.S. have suffered from a psychological disorder at some time in their lives.
Step-by-step explanation:
The approximate total percentage of adults in the U.S. who have suffered from a psychological disorder at some time in their lives is c) 50%. This is because various sources indicate that different types of mental disorders affect a significant portion of the population. For instance, anxiety disorders alone affect 28 percent of U.S. adults over a lifetime, while mood disorders, including major depression and bipolar disorder, affect 21 percent over a lifetime.
When considering the prevalence of mental disorders and the fact that some individuals may experience more than one type of disorder, it can be estimated that approximately half of the adult population in the U.S. will encounter a psychological disorder at some point in their lives.