If the Corporate Tax Rate Were to Increase, One Would

If the corporate tax rate were to increase, one would expect a firm's depreciation tax shield to be which of the following, all else the same?

A) More valuable.
B) Less valuable.
C) Unchanged, since depreciation doesn't change.
D) Unchanged, because changes in tax rates don't matter once a project is in place.
E) It is impossible to tell how it will change, if at all, without more information.