Suppose you want to verify that the user has entered a value into a text box named txtInput. Which of the following code segments responds with an appropriate message if the user does not enter a value? a. if txtinput. Text="" Then lblStatus. Text="no data has been entered" End if. b. if txtinput. Text<>" " Then lblStatus. Text="no data has been entered" End if. c. if txtinput. Text<> String. Empty Then lblStatus. Text="no data has been entered" End if. d. if txtinput. Text=string. EmptyThen lblStatus. Text="no data has been entered" End if.