The correct definition of bioavailability is : ( A ) The proportion of a drug that has an active effect because it enters the circulation when taken into the body
This is the proportion of a substance that gets absorbed into circulation in the body when ingested or introduced into the body. When it goes into circulation the substance has an active effect in the body.
Hence bioavailability is The proportion of a drug that has an active effect because it enters the circulation when taken into the body.
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