A biotechnology firm...?

Question

A biotechnology firm has produced tobacco plants that synthesize human antibodies that prevent bacterial diseases. One of the first steps in the production of these plants required

1.using natural selection to increase the survival of antibody-producing tobacco plants

2.inserting human DNA segments into the cells of tobacco plants

3.using selective breeding to increase the number of antibody genes in tobacco plants

4.growing tobacco plants in soil containing a specific fertilizer

Answer 1

number 2. I just took a test and this question was on it. ^^