During a quality random inspection, the director of a factory asked the inspection leader: "Our factory has always attached great importance to quality. The products we inspected are probably qualified?" It may be true, but the second half is incorrect. ". According to the quality inspection leadership, Which of the following must be true? ["I'm not sure if you value quality, but this time you check that your factory has unqualified products.", 'Most products are qualified, few are not.', 'Some products are qualified, some products are not qualified.', 'Attention to quality is not necessarily related to product qualification.']