Select the correct statement.

Penicillium notatum restrict the growth of Staphylococci. Acetobacter aceti produces acetic acid. Saccharomyces cerevisiae is used for commercial production of ethanol. Streptococcus produces streptokinase which is modified by genetic engineering to be used as a 'clot buster' for removing clots from the blood vessels of patients who have undergone myocardial infarction leading to heart attack. Bacteria which produce methane are collectively called methanogens, and one such common bacterium is Methanobacterium. These bacteria are commonly found in the anaerobic sludge during sewage treatment.