Indiana imposes a one percent property tax on grocery stores built before 1970 and a five percent ...

Indiana imposes a one percent property tax on grocery stores built before 1970 and a five percent property tax on grocery stores built after 1970 . The different tax rates are probably:
 a. unconstitutional; they violate the commerce clause protection of interstate commerce
  b. constitutional; they do not violate the commerce clause protection of interstate commerce
  c. unconstitutional; they violate the right of Congress to regulate interstate and intrastate commerce d. unconstitutional; they violate the equal protection clause of the Fourteenth Amendment
  e. none of the other choices