What should be the accuracy of automatic moisture control for manufacturing sands?

• A. ¬¨¬®¬¨¬± 0.1%
• B. ¬¨¬®¬¨¬± 0.2%
• C. ¬¨¬®¬¨¬± 0.3%
• D. ¬¨¬®¬¨¬± 0.4%