Answer:
The correct answer is letter "D": Some apps will work on different OS platforms, but many will not.
Explanation:
Devices using Android, iOS, and Windows Mobile Operating Systems (OS) use dedicated apps for each OS. OS providers reserve some of their key apps to the exclusive use of their devices which makes them different one from another and creates users having a bias on certain OS.
Thus, if the manager of a company is looking for standardizing all mobile applications across different OS, that is unlikely to be possible since some apps are compatible while others are not.