Q. A hollow saddle key is

• (A) A taper key which fits half in the key way of hub and half in the key way of shaft
• (B) A taper key which fits in a key way of the hub and is flat on the shaft
• (C) A taper key which fits in a key way of the hub and the bottom of the key is shaped to fit the curved surface of the shaft
• (D) Provided in pairs at right angles and each key is to withstand torsion in one direction only