As used in the last paragraph of this passage, the word intricate means ______

A．nitinol is an organic metal
B．nitinol is stronger than any metal
C．nitinol's sensitivity to temperature changes makes it impractical for most uses
D．nitinol is better than stainless steel in jobs that require constant stress on the metal

A．The metal is shaped into ingots.
B．The metal is separated into nickel and titanium.
C．The metal is drawn into a wire.
D．The metal is set in its desired curve or shape and heated briefly.