when we Declaring a variable before programming start it is called as . . . . . . . . it tells Visual Basic to reserve space in memory.

The correct answer is: A. explicit declaring

Explicit declaring is when a variable is declared before it is used in a program. This tells Visual Basic to reserve space in memory for the variable.

Implicit declaring is when a variable is declared as it is used in a program. This does not tell Visual Basic to reserve space in memory for the variable, and it can lead to errors if the variable is not used correctly.

Public declaring is when a variable is declared as public, which means that it can be accessed from anywhere in the program.

Local declaring is when a variable is declared as local, which means that it can only be accessed from the function or procedure in which it is declared.

Here is an example of explicit declaring:

Dim myVar As Integer

Here is an example of implicit declaring:

myVar = 10

Here is an example of public declaring:

Public myVar As Integer

Here is an example of local declaring:

Sub MyProcedure()
Dim myVar As Integer
myVar = 10
End Sub