One way to detect alternative splicing of transcripts from a given gene is to _____.
A. compare the sequences of different mRNAs made from the given gene
B. measure the relative rates of transcription of the given gene compared to that of a gene known to be constitutively spliced
C. compare the DNA sequence of the given gene to that of a similar gene in a related organism
D. compare the sequences of different primary transcripts made from the given gene