Two shafts 'A' and 'B' have the same material. The shaft 'A' is solid of diameter 100 mm. The shaft 'B' is hollow with outer diameter 100 mm and inner diameter 50 mm. The torque transmitted by shaft 'B' is __________ as that of shaft 'A'.

• 1/6
• 1/8
• 1/4
• 15/16