How does the Extended Get Digit String step differ from the Get Digit String? （）

• A、It can be used in conjunction with another step. 
• B、It allows the application programmer into another section of the application. 
• C、Most of the Extended Get Digit String variables can be changed while the application is running. 
• D、It allows the entry of a Boolean expression for the Interruptible and Clear DTMF Buffer on Retry fields.