Final answer:
The first antibiotic, penicillin, was discovered by Alexander Fleming in 1928. He identified its antibacterial properties against various harmful bacteria. However, the isolation, purification and mass production of penicillin were later accomplished by researchers Howard Florey and Ernst Chain.
Step-by-step explanation:
The individual attributed with the discovery of the first antibiotic, penicillin, is Alexander Fleming (Answer choice C). This discovery occurred in 1928 when Fleming noticed that a mold growth (a strain of Penicillium notatum) which had contaminated his petri dish, had inhibited the growth of staphylococci bacteria. This crucial observation led to further research and confirmed that penicillin, derived from the mold, had antibacterial properties against several types of harmful bacteria.
It's important to note that although Fleming is recognized for discovering and identifying penicillin, its successful isolation, purification, and mass production were later accomplished by Howard Florey and Ernst Chain at Oxford University. For their significant contributions, Fleming, Florey, and Chain were awarded the Nobel Prize in Physiology and Medicine in 1945.
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