During the course of the Fifth Generation, several advancements occurred in the computer industry. These advancements revolutionized the way computers were used and made them more accessible to the general public. Two significant developments during this period were the availability of powerful computers at affordable prices and the introduction of touch screens in computer architecture.

Availability of powerful computers at affordable prices:
The Fifth Generation witnessed a major breakthrough in computer technology with the availability of powerful computers at cheap rates. This development made it possible for individuals and organizations to own and use high-performance computers without breaking the bank. The reduced cost of these computers was primarily due to advancements in semiconductor technology and increased competition among computer manufacturers.

Introduction of touch screens in computer architecture:
Another significant development during the Fifth Generation was the introduction of touch screens in computer architecture. Touch screens enabled users to interact directly with the computer screen by touching it, eliminating the need for external input devices such as keyboards and mice. This innovation brought about a more intuitive and user-friendly interface, making computers more accessible to a wider range of individuals.

Increased complexity and specialized knowledge:
While the availability of powerful computers at affordable prices and the introduction of touch screens were major advancements, it also brought about increased complexity in computer systems. As computers became more advanced, ordinary people without technical support or degrees in electronics found it challenging to assemble and troubleshoot computers on their own. This complexity necessitated the need for technical support and specialized knowledge to effectively use and maintain these advanced systems.

Conclusion:
In conclusion, the Fifth Generation witnessed the arrival of powerful computers at cheap rates and the introduction of touch screens in computer architecture. These developments made computers more accessible and user-friendly. However, the increased complexity of these systems also made it difficult for ordinary people to assemble and maintain computers without technical support or specialized knowledge. Therefore, the correct answer is option D, which states that both a) the world saw the arrival of powerful computers at cheap rates, and b) touch screens arrived in computer architecture.