Correct option is (B) \(\frac{5\rho}8\)
Let density of \(\rho_B\)
VA\(\rho\)n + VB\(\rho_B\) g = V\(\rho\)g
\(\frac43\)πR3 4\(\rho\)g + \(\frac43\)π(2R)3\(\rho\)g = V\(\rho\)g
\(\frac43\)πR3 4 \(\rho\)g + \(\frac43\)π(8R3) \(\rho_B\)g = \(\frac43\)πR3\(\rho\)g
4\(\rho\) + 8\(\rho\)B = 9\(\rho\)
8\(\rho\)B = 9\(\rho\) - 4\(\rho\)
\(\rho\)B = \(\frac{5\rho}8\)