I think A and C are the correct answers. The 'Read' button is used to capture dynamic values that can be stored as variables or used for data binding later on.
I also think we press the 'Read' button to capture text in a message screen that can be used for data binding later. It helps in maintaining data integrity.
Rory
7 days agoLeota
8 days agoVan
24 days agoVincenza
26 days agoMickie
27 days ago