The correct option is D 9
The equivalent mass of the metal is the number of parts by mass of metal that combines with 79.9 parts by mass of bromine.
1.0 g of metal combines with 8.89 g of bromine.
Hence, the mass of metal that combines with 79.9 g of bromine is 79.98.89×1=9 g.
Hence, the equivalent weight of metal is 9.