Statement I: Correct. Streptokinase is an enzyme produced by \textit{Streptococcus} and used as a clot buster.
Statement II: Correct. \textit{Saccharomyces cerevisiae} (yeast) is used for ethanol production in industries.
Statement III: Incorrect. Cyclosporin-A is an immunosuppressive drug, not a cholesterol-lowering agent, and is produced by \textit{Trichoderma polysporum}.
Statement IV: Correct. Statins, which lower cholesterol, are produced by yeast species like \textit{Monascus purpureus}.