Correct Response: A. When choosing materials for structural members of an aircraft, the two most important considerations are strength and weight. The thrust of the motors and the long spans of the wings make strength critical in airplane design. At the same time, every extra pound translates into extra fuel usage since, unlike with land and sea vehicles, there is nothing but the power of the engines to support all of the weight. Plasticity (B and D) and elasticity (C and D) are also important factors to be taken into account. However, they do not rank as high in importance as strength and weight.
