Up to what temperatures are high alloy steels heated before treating them by oxygen cutting?

• A. 675¬¨¬®‚Äö√†√ªC
• B. 725¬¨¬®‚Äö√†√ªC
• C. 775¬¨¬®‚Äö√†√ªC
• D. 825¬¨¬®‚Äö√†√ªC