Which of these must occur during s phase of the cell cycle so that two daughter cells can be produced during m phase? (1 point) a-the dna must be replicated. b-the chromosomes must be joined. c-the cytoplasm must be separated. d-the cell membrane must be expanded,

During the S phase in the cell cycle, the chromosomes are replicated so that there are two copies. These copies are necessary so that each daughter cell created during the M phase will have an identical copy of the DNA.

Therefore, the answer is A: The DNA must be replicated. 

The chromosomes joining, cell membrane expanding, and cytoplasm separating all happen during the M phase (mitosis).

Answer is below

Step-by-step explanation:

Rewrite equations

Solve 2x+3y=−1 for x

(Add -3y to both sides)

Substitute

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