What can we know from Dr. Blaser and his studies？A．People haven"t identified the long-term

What can we know from Dr. Blaser and his studies？

A．People haven"t identified the long-term bad effects of antibiotics.

B．Alterations in the microbiome are found to be linked to many diseases.

C．He found people of all ages showed increased weight gain by using antibiotics.

D．He found an association between childhood antibiotic treatment and the later disease.

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