The stresses developed in concrete and steel in reinforced concrete beam 25 cm width and 70 cm effective depth, are 62.5 kg/cm2 and 250 kg/cm2 respectively. If m = 15, the depth of its neutral axis is

• A. 20 cm
• B. 25 cm
• C. 30 cm
• D. 35 cm
• E. 40 cm