Grammar Error in "When individual family members are exposed to and adopt the new ideas, the tendency is for conflict to rise and for those in conflict to become psychologically separated from each other."

The grammar error in the sentence is the use of 'those' as a pronoun without a clear antecedent. It is not clear who 'those' is referring to in the sentence. To correct this error, you could replace 'those' with a more specific noun phrase, such as 'the family members in conflict' or 'those experiencing the conflict.'