The correct response is:
The amount of the gravitational force doubles.
According to the law of universal gravitation, the gravitational force \( F \) between two objects is directly proportional to the product of their masses \( m_1 \) and \( m_2 \), and inversely proportional to the square of the distance \( r \) between them:
\[ F = \frac{G \cdot m_1 \cdot m_2}{r^2} \]
If the mass of one object doubles while the other object's mass and the distance between them remain the same, the gravitational force will also double.