What happened the day after researchers put two antibiotics in the test tube containing E.

What happened the day after researchers put two antibiotics in the test tube containing E.coli？

A．The two antibiotics began to work against each other.

B．Most of the E.coli were killed by the antibiotics.

C．E.coli showed a kind of resistance towards the drugs.

D．The population of E.coli began to grow dramatically.

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