4. Which of the following does not apply to the construction or use of a DNA library?
(A) Determining the location of a particular DNA sequence in a DNA library
requires a suitable hybridization probe.
(B) Genomic libraries are better for expressing gene products than cDNA libraries.
(C) Many segments of DNA from a cellular genome are cloned.
(D) Specialized DNA libraries can be made by cloning DNA copies of mRNAs.
(E) The DNA copies of mRNA found in a cDNA library are made by reverse
transcriptase.