Which of the following accurately describes semiconductor diodes? A. Unlike junction diodes, point-contact diodes are enclosed in a suitable casing and have terminals for connecting them to a circuit. B. Point-contact diodes are more likely to be used as rectifiers than junction diodes. C. Unlike point-contact diodes, junction diodes utilize a point of metal wire in contact with a single wafer of P-type or N-type material. D. Junction diodes are preferred over point-contact diodes for most purposes.

The correct option is D

Junction diodes are preferred over point-contact diodes for most purposes.

Explanation:

Point contact diode:

This type of diode is constructed by touching a metallic wire with an N-type semiconductor to form a small area of contact, hence the name point contact diode. The switching speed of these diodes is better than a conventional diodes.

These diodes are not usually preferred due to their low current ratings and poor reliability.

P-N junction diode:

This type of diode is constructed by joining two regions of opposite conductivity N-type and P-type material, a PN-junction is formed which allows the current to flow in one direction only. The conversion of AC current to DC is done by this process called rectification.

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