From the description of the substances, the best answer would be option A. Substance D would generally function as a solvent because it has the largest composition in a solution. A solvent in a solution has the highest percent composition among all components involved. Having a composition of more than 50% would mean that a substance is the solvent.
The answer is A. Force is equal to mass x acceleration. The acceleration due to gravity is a constant so multiplying the mass by 2 would double the force.
