When the supreme court declares a law that was created by congress unconstitutional, it is an example of ? ?

When the Supreme Court declares a law that was created by Congress unconstitutional, it is an example of "judicial review", since this is one of the ways in which the Supreme Court "checks" the other branches of government. 

“destroyers for bases agreement in the destroyers for bases agreement between the united states and the united kingdom on september 2, 1940, fifty caldwell , wickes, and clemson class us navy destroyers were transferred to the toyalbnavy from the united states navy in exchange for land rights on british possessions.” i hope this you .