試題詳解

15. The production of recombinant DNA (DNA cloning) involves the following 4 steps.

Step 1: Preparation of fragments of foreign DNA.

Step 2: Insertion of foreign DNA fragment into a cloning plasmid.

Step 3: Introduction of recombinant DNA into a recipient cell for replication.

Step4: Selection of cells containing the correct recombinant DNA.

Among them, step   （Ａ）   involves PCR reaction and step   （B）   usually requires the use of antibiotics.   （Ａ） and  （B）  correspond to
(A) 1 and 3
(B)2 and 4
(C) 1 and 4
(D) 2 and 3
(E) 3 and 4