Recombinant DNA is force to enter the host cells by incubating the cells with rDNA first

Options

A. On ice followed by heat shock and then again on ice
B. At low temperature followed by heat shock and then on ice
C. In ethidium bromide followed by calcium salts
D. Into chilled ethanol followed by ice and then into CsCl

Answer

a

Explanation

The host cells with r-DNA are first subjected to ice followed by heat shoch `(42^(@)C)` and then to ice. As a result, rDNA molcules are easily introduced into the host cells. This process is called transformation.