6. 下列实验的对应操作中，不合理的是
<table><tr><td><img src="https://zebfdsytobcavmuynuhx.supabase.co/storage/v1/object/public/review-images/tasks/77195b74-3abe-42e9-8d31-1d249a2e71c4/a7dc78bd705d912e.jpg"/></td><td><img src="https://zebfdsytobcavmuynuhx.supabase.co/storage/v1/object/public/review-images/tasks/77195b74-3abe-42e9-8d31-1d249a2e71c4/c091bef1c1cfbace.jpg"/></td></tr><tr><td>A. 用HCl标准溶液滴定NaOH溶液</td><td>B. 稀释浓硫酸</td></tr><tr><td><img src="https://zebfdsytobcavmuynuhx.supabase.co/storage/v1/object/public/review-images/tasks/77195b74-3abe-42e9-8d31-1d249a2e71c4/28ef33de3847ea25.jpg"/></td><td><img src="https://zebfdsytobcavmuynuhx.supabase.co/storage/v1/object/public/review-images/tasks/77195b74-3abe-42e9-8d31-1d249a2e71c4/def067de63aaa5b0.jpg"/></td></tr><tr><td>C. 从提纯后的NaCl溶液获得NaCl晶体</td><td>D. 配制一定物质的量浓度的KCl溶液</td></tr></table>
D