Answer:
The answer to the question: Which trait is not a characteristic of the International Style, would be: A: Subtle colors.
Step-by-step explanation:
The International Style was an arquitectonic trend that appeared around the 1920's and 1930´s and that was characterized by the use of industrial materials such as glass and steel, to build structures that reflected a sense of utility, rather than beauty or comfort. As such, color was not one of the primary objects of this type of construction and that is why this is the correct choice.