To solve this problem, we need to understand the role of chilled ethanol in the purification process of recombinant DNA technology.$\newline$During this process, chilled ethanol is used to precipitate nucleic acids from a solution.$\newline$Let's analyze the options:$\newline \bullet$Option 1: RNA - RNA can be precipitated by ethanol, but it is not the primary target in recombinant DNA purification.$\newline \bullet$Option 2: DNA - DNA is the primary target for precipitation in recombinant DNA technology. Chilled ethanol helps in precipitating DNA by reducing its solubility.$\newline \bullet$Option 3: Histones - Histones are proteins and are not precipitated by ethanol in this context.$\newline \bullet$Option 4: Polysaccharides - Polysaccharides are not the primary target for ethanol precipitation in this process.$\newline$Therefore, the correct answer is Option 2: DNA.$\newline$Chilled ethanol is used to selectively precipitate DNA, making it easier to separate from other cellular components.$\newline$Thus, the correct option is Option 2.