The force of attraction between two unit point masses separated by a unit distance is called:

Universal gravitational constant

The correct answer is Option (1) → Universal gravitational constant

According to Newton’s law of gravitation:

$F = G \frac{m_1 m_2}{r^2}$​​

If $m_1 = m_2 = 1 \, \text{kg}$ and $r = 1 \, \text{m}$, then

$F = G$

So, the force of attraction between two unit masses at unit distance is called the universal gravitational constant (G).