Semi-conservative DNA replication in prokaryotes

Steps:

• Identify key features of semi-conservative replication: each new DNA molecule has one parental and one new strand.
• Recall prokaryotic specifics: circular DNA, single origin of replication, bidirectional replication.
• Evaluate statements against these: typically 2 statements align (e.g., parental strand retention, equal strand distribution).
• Count matching statements: exactly 2 fit the model.

Why B is correct:

• Semi-conservative model, proven by Meselson-Stahl experiment, conserves one parental strand per daughter DNA, matching 2 standard statements on strand inheritance and replication fidelity.

Why the others are wrong:

• A: Underestimates; at least 2 core statements (strand conservation, no full parental retention) apply.
• C: Overestimates; prokaryotic replication has only 2 definitive semi-conservative traits, not 3.
• D: Incorrect; full 4 statements would imply dispersive or conservative models, not semi-conservative.

Final answer: B