The logical expression $X$, in its simplest form for the truth table
is

• Correct answer
  A

  $\mathrm{X}=\mathrm{a} . \mathrm{b}$
• B

  $X=a+b$
• C

  $\mathrm{X}=\mathrm{a}^{\prime} \mathrm{b}$
• D

  $\mathrm{X}=\mathrm{a} \cdot \mathrm{b}^{\prime}$

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