A circular shaft is subjected to the combined action of bending, twisting and direct axial loading. The maximum bending stress \[\sigma \]maximum shearing stress \[\sqrt{3\sigma }\] and a uniform axial stress \[\sigma \](compressive) are produced. The \[\sigma \]maximum compressive normal stress produced in the shaft will be

• A. \[3\,\sigma \]
• B. \[2\,\sigma \]
• C. \[\sigma \]
• D. Zero