Strontium crystallizes in a fcc unit cell with edge length $\text{a}\text{.}$ It contains $\text{0}\text{.2\%}$ Frenkel defect and another crystal of $\text{Sr}$ contains $\text{0}\text{.1\%}$ Schottky defect. Density of solid with Frankel defect = ${\text{d}}_{\text{f}}$ and density with Schottky defect = ${\text{d}}_{\text{s}},$ then

• A

  ${\mathrm{d}}_{\mathrm{f}}={\mathrm{d}}_{\mathrm{s}}$
• Correct answer
  B

  ${\mathrm{d}}_{\mathrm{f}}>{\mathrm{d}}_{\mathrm{s}}$
• C

  ${\mathrm{d}}_{\mathrm{f}}<{\mathrm{d}}_{\mathrm{s}}$
• D

  ${\mathrm{d}}_{\mathrm{f}}=2{\mathrm{d}}_{\mathrm{s}}$

Hence, the correct answer is option: 'B'.