Final answer:
In 4000 series CMOS technology, the pin connected to the positive power supply is most appropriately labeled VDD but can also be referred to as VCC, which is more common in bipolar circuits.
Step-by-step explanation:
When using 4000 series CMOS technology, the pin labeled that is connected to the positive power supply is typically labeled VDD or VCC. However, in the context of CMOS devices, VDD is more commonly used and is the correct answer. The label VCC is traditionally associated with bipolar circuits and represents the Collector supply voltage in bipolar junction transistors (BJTs). In contrast, GND is used to denote the Ground pin, IN represents an input pin, and OUT denotes an output pin.