A CsCl gradient will separate DNA molecules by

✅ Explanation:
-Density gradient centrifugation is a technique where a solution of varying density is created (in this case, using CsCl). When a mixture of molecules is centrifuged in this gradient, each molecule will migrate to a position in the tube where its density matches the density of the surrounding solution. This allows for the separation of molecules based on their density differences.
-DNA molecules can have slightly different densities based on their base composition (GC content) or the presence of isotopes. CsCl density gradient centrifugation is a powerful technique to separate DNA molecules based on these subtle density differences.