What does the MutableLiveData class allow you to do?

The MutableLiveData class is a key component in Android's architecture components, specifically designed to hold and manage data that can be observed. The primary feature of MutableLiveData is its ability to allow modification of the data it encapsulates. This means that when you have an instance of MutableLiveData, you can change its value, and those changes will be notified to any active observers.

This is particularly valuable in the context of the MVVM (Model-View-ViewModel) design pattern used in Android development, where the ViewModel can update the UI by simply updating the MutableLiveData. Whenever the data changes, any observers registered to that MutableLiveData are automatically notified, prompting them to react accordingly, for example, by refreshing a user interface element.

In contrast, other options do not accurately represent what MutableLiveData is specifically designed for. It does not simply observe live data; that is a characteristic of LiveData in general. While it can be part of a solution to combine live data, that is not the primary function of MutableLiveData itself. Storing non-live data is also outside the scope of what MutableLiveData is intended for, as it is intrinsically about handling live data that can change over time.