A recombinant DNA molecule is produced by

A recombinant DNA molecule is produced by "genetic recombination laboratory methods".

Explanation:

The genetic recombination laboratory methods like molecular cloning is responsible for rDNA molecules formation. The steps involve pooling of genetic material from number of sources and generate very unique sequences which is not available in the genome.

The another method used for recombinant DNA molecule production is Polymerase chain reaction (PCR). This involves millions to billions of copies of a single DNA sample which allows easy access for scientists to take minute amount of DNA sample and make it to a appropriate large amount, as needed to follow deep analysis.