D. Man-Made is the answer
<span>Lactation is different between monotremes and therian mammals because monotremes are oviparous and have cloaca . Oviparous means they lay eggs, and generally animals that lay eggs do not nurse their young or lactate. Therian mammals give live birth, these are the animals that use breast milk to nurse their young.</span>
Well its easy the Bt gene is inserted into one plant cell by using a bacterial plasma.
