Correct Answer - B
Let B be the original base.
`2B+H_2PtCl_6rarrB_2H_2PtCl_6overset(triangle)toPt`
Ew of `B_2H_2PtCL_6=2B+2+195+6xx35.5`
`=2B+410`
`("weight of chloroplati nate")/("weight of Pt")=("Eq. wt. of salt")/("Eq. wt. of Pt")`
`(0.3)/(0.09)=(2B+410)/(195)`
`B(Ew)` of base `=120`
Molecular weight of base `=Ewxx`acidity
`=120xx2=240`