A scientist is troubleshooting the synthesis of a cDNA library. The scientist performs both a Northern and a Southern blot. The Northern blot demonstrated the presence of RNA while the Southern blot indicated that no cDNA was present in the sample. What is likely to be the cause of the failed synthesis of the cDNA library? a.) proper primers
b.) temperature too cold for annealing
c.) defective reverse transcriptase
d.) too many dNTPs