Two objects A and B of masses 1 g and 4 g respectively are moving with equal kinetic energies. The ratio of the magnitudes of their linear momenta is:

The correct option is C $1:2$
They both have equal kinetic energy. i.e.
$\frac{1}{2}{m}_A{v}_A^2=\frac{1}{2}{m}_B{v}_B^2$

$\Rightarrow \frac{p_A}{p_B}=\sqrt{\frac{2m_{A}E}{2m_{B}E}}=\sqrt{\frac{m_A}{m_B}}=\sqrt{\frac{1}{4}}=\frac{1}{2}$

So the ratio of their linear momentum is $1:2$