Final answer:
When merging two similar cases with different parent cases, typically Case1 is merged into Case2; activities and notes are combined under Case2, and Case1's details are subsumed.
Step-by-step explanation:
When attempting to merge two cases in a case management system, particularly when they have different parent cases, it typically depends on the rules of the case management system. However, generally speaking, when you merge Case1 into Case2, the usual result is option A: Case1 is merged into Case2 and the activities and notes from Case1 are combined under Case2. This means that all the information from Case1 will be transferred to Case2, which will be the surviving case record after the merge. Both cases will not become child cases of the same parent (option B is incorrect), and they will not remain parented to their original records post-merge (option C is incorrect). Additionally, since Case2 is the destination of the merge, option D is also incorrect because the activities and notes do not become combined under Case1.