To solve this problem, we need to identify the microorganism responsible for producing the immunosuppressive molecule cyclosporin A.$\newline$Let's analyze each option:$\newline \bullet$Option 1: Trichoderma polysporum$\newline$ - Trichoderma polysporum is a fungus known for producing cyclosporin A, an immunosuppressive drug used in organ transplantation.$\newline$ - This matches the requirement of the question.$\newline \bullet$Option 2: Clostridium butylicum$\newline$ - Clostridium butylicum is a bacterium used in the production of butyric acid, not cyclosporin A.$\newline \bullet$Option 3: Aspergillus niger$\newline$ - Aspergillus niger is a fungus used in the production of citric acid, not cyclosporin A.$\newline \bullet$Option 4: Streptococcus cerevisiae$\newline$ - Streptococcus cerevisiae is not a recognized species; it seems to be a mix-up of Saccharomyces cerevisiae, a yeast used in baking and brewing, not in cyclosporin A production.$\newline$Based on the analysis, the correct microorganism responsible for the production of cyclosporin A is Trichoderma polysporum.$\newline$Therefore, the correct option is Option 1.