Final answer:
The correct answer to the oligonucleotide treatment with EcoRI is that it would produce two oligonucleotides with a total of 25 nucleotides, including sticky ends. There appears to be a typo in the provided options.
Step-by-step explanation:
Treatment of the oligonucleotide 5'-CAGTCGATACAGAATTCGTACCTAG-3' with the restriction enzyme EcoRI, which recognizes the sequence 5'-G|AATTC-3', will produce two oligonucleotides.
This is because EcoRI cuts at the palindromic site within the sequence, resulting in DNA fragments with sticky ends. To determine the size of the fragments, count the nucleotides on either side of the EcoRI cleavage site.
After cleavage, we have: 5'-CAGTCGATACA|G AATTCGTACCTAG-3'. The left fragment has 12 nucleotides up to the cut and includes the 'G' at the cleavage site (13 including the 'G'). The right fragment has 11 nucleotides after the 'G' at the cleavage site (12 including the 'G'), so the sizes of the oligonucleotides would be 13 and 12, respectively.
Therefore, the correct answer is: (b) 15; sticky, since the sum of 13 and 12 nucleotides in the two oligonucleotides equals 25 (however, this appears to be a typo, as the provided options do not include 25); nonetheless, the ends produced are sticky ends.