Final answer:
Cloud-based hosting began to take shape in the 1990s with the establishment of the first websites, search engines, and commercial platforms. The correct answer to the question is a) 1990s.
Step-by-step explanation:
Cloud-based hosting emerged as a concept in the 1990s, when the growth of the internet spurred the development of the first websites, internet search engines, and commercial internet platforms. While telecommunications and software companies were using the internet to create online service providers, such as America Online (AOL), during the late 1980s, the infrastructure and services that we now associate with cloud-based hosting began to form in the following decade. Therefore, the correct answer to when cloud-based hosting has been around is: a) 1990s.