【单选题】A mutant of E. coli with a heat-sensitive DNA ligase (25℃ permissive, 37℃ nonpermissive) has been used to show that DNA synthesis is discontinuous. Examination of DNA replication in the presence of [3...
A.
The accumulation of short segments of unlabeled DNA at 25 ℃ and at 37 ℃ .
B.
The accumulation of short segments of unlabeled DNA at 25 ℃ but not at 37 ℃ .
C.
The accumulation of short segments of radioactive DNA at 37 ℃ but not at 25 ℃.
D.
The incorporation of short fragments of radioactive DNA into longer ones at 25 ℃ and at 37 ℃ .