How to explicitly set an Option which is a tuple of a certain type to be None?

```
scala> var c = Some(1,1)
c: Some[(Int, Int)] = Some((1,1))

scala> c = None
<console>:11: error: type mismatch;
 found   : None.type
 required: Some[(Int, Int)]
       c = None
           ^

scala> None()
<console>:11: error: None.type does not take parameters
       None()
           ^

scala> c = None()
<console>:11: error: None.type does not take parameters
       c = None()
               ^

scala> c = None.Int
<console>:11: error: value Int is not a member of object None
       c = None.Int
                ^

scala> c = None(Int, Int)
<console>:11: error: None.type does not take parameters
       c = None(Int, Int)
               ^

scala> c = (None, None)
<console>:11: error: type mismatch;
 found   : (None.type, None.type)
 required: Some[(Int, Int)]
       c = (None, None)

```