What Dictates Whether It Is Appropriate to Host Application Server

What dictates whether it is appropriate to host Application Server services for different environments on a single device? (Select 2)

A) Whether the different environments will be accessing the same processes
B) Whether there are any security related reasons to segregate services on to separate devices
C) Whether it is acceptable for product updates to be applied to all environments simultaneously
D) It is not possible to host multiple Application Server services on a single device