Molar mass of sucrose = C₁₂H₂₂O₁₁

= 12× 12 + 1× 22 + 16 × 11 = 342g/mol

⇒

⇒ Number of moles = 0.01

Sucrose (C₁₂H₂₂O₁₁) contains 11 oxygen atoms

⇒ 11 × 6.022 × 10²³

For 0.01 moles of sucrose

⇒ 0.01 × 11 × 6.022 × 10²³= 6.6 × 10²²

Now, Molar mass of water = H₂O = 2× 1 + 16 = 18g/mol

⇒

⇒ Number of moles = 1

Sucrose (H₂O) contains 1 oxygen atom = 6.022 × 10²³

For 1 mole of water = 6.022 × 10²³

Now, add the both values: 6.6 × 10²²+ 6.022 × 10²³

We get 6.68 × 10²³ atoms. Hence, the option (a) is correct.