tempo-insert-region

tempo-insert-region is a variable defined in `tempo.el'.
Its value is

nil

Documentation:
Automatically insert current region when there is a `r' in the template
If this variable is nil, `r' elements will be treated just like `p'
elements, unless the template function is given a prefix (or a non-nil
argument). If this variable is non-nil, the behavior is reversed.

In Transient Mark mode, this option is unused.

You can customize this variable.