Following are the steps involved in the process of PCR. A. Annealing B. Amplification ( $\sim 1$ billion times) C. Denaturation D. Treatment with Taq polymerase and deoxynucleotides E. Extension Choose the correct sequence of steps of PCR from the options given below :

• Correct answer
  A

  $\mathrm{C} \rightarrow \mathrm{A} \rightarrow \mathrm{D} \rightarrow \mathrm{E} \rightarrow \mathrm{B}$
• B

  $\mathrm{A} \rightarrow \mathrm{B} \rightarrow \mathrm{E} \rightarrow \mathrm{D} \rightarrow \mathrm{C}$
• C

  $\mathrm{A} \rightarrow \mathrm{C} \rightarrow \mathrm{E} \rightarrow \mathrm{D} \rightarrow \mathrm{B}$
• D

  $\mathrm{D} \rightarrow \mathrm{B} \rightarrow \mathrm{E} \rightarrow \mathrm{C} \rightarrow \mathrm{A}$

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