attempt to explain personality and differences among people in terms of personal characteristics that are stable across situations.

The answer is Trait theories.

Explanation:

In terms of psychology, trait theory refers to an approach related to the study of aspects concerning human personality. Trait theorists' interest is especially related to the measurement of traits. This measurement has a relationship with aspects like habitual patterns of behavior, thought, as well as emotion.

Traits have a close relationship with different aspects of personality that are considered stable over time. They are different according to the individuals, but they are considered consistent regarding the situations, as well as they also affect behavior.  

early settlements on the subcontinent. both the indus and the ganges rivers carried rich silt from the mountains to the plains. when the rivers flooded, the silt spread over the plains and made the soil in the river valleys fertile for farming.

answer; by working independently, the states have a high likelihood of developing innovative solutions that can be employed in other states;