Your company has purchased another company that also uses Windows Server 2016 and Active Directory. Both companies need to be able to access each other's forest resources. How can you achieve this goal with the least administrative effort?

Create a two-way forest trust

Explanation:

The aim here is to ensure that both companies are able to access the forest resources of each other. The creation of a Two-way Forest Trust would guarantee that as if the Two-way Forest Trust is created between Forest A and Forest B, being the forest resources of the two companies respectively, then all the domains in Forest A will trust every domain in Forest B and vice versa.

i'm so sorry that's not a question and this isn't an answer

that without the operating systems you would have to control and synchronize computer hardware.