The heavy three-, four-, or six-sided length of pipe suspended from the swivel through the rotary table and connected to the topmost joint of drill pipe to turn the drill stem as the rotary table turns is called the __________.

Correct Answer: Option D — kelly

The kelly is a heavy, multi-sided pipe that transmits torque from the rotary table to the drill string. By sliding through the kelly bushing, it allows the drill string to rotate while simultaneously permitting the string to move vertically downward as the hole is deepened during the drilling process.