Silica covers an entire group of minerals, which have the general formula `SiO_2`, the most common of which is quartz, which is a framework silicate with `SiO_4` tetrahedra arranged in spirals. The spirals can turn in a clockwise or anticlockwise direction resulting in two mirror images, optically active, varieties of quartz.
The following structures represent various silicate anions. Their formulas are respectively

Options

A. `SiO_3^(2-) and Si_3O_7^(2-)`
B. `SiO_4^(4-) and Si_3O_9^(6-)`
C. `SiO_4^(2-) and Si_3O_6^(2-) `
D. `SiO_3^(4-) and Si_3O_7^(8)`

Answer

B

Explanation

`SiO_4^(4-) and Si_3O_10^(2-)`