C# Error CS1605 – Cannot use ‘{0}’ as a ref or out value because it is read-only

C# Error

CS1605 – Cannot use ‘{0}’ as a ref or out value because it is read-only

Reason for the Error & Solution

Cannot pass ‘var’ as a ref or out argument because it is read-only

A variable passed as a or parameter is expected to be modified in the called method. Therefore, it is not possible to pass a read-only parameter as ref or out.