Assertion (A) : $\mathrm{NaCl}$ is less soluble in heavy water than in ordinary water. Reason (R) : Dielectric constant of ordinary water is more than that of heavy water. The correct answer is

• Correct answer
  A

  Both (A) and (R) are true and (R) is the correct explanation of (A)
• B

  Both $(\mathrm{A})$ and $(\mathrm{R})$ are true but $(\mathrm{R})$ is not the correct explanation of (A)
• C

  (A) is true, but (R) is not true
• D

  (A) is not true, but (R) is true

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