I believe the correct answer from the choices listed above is option A. Harry Hess used new technologies made available in the 1950s to observe and measure seafloor spreading. Harry Hess<span> describes the theory of sea-floor spreading. Hope this answers the question.</span>
According to the theory of Harry Hess, seafloor spreading hypothesis is described as formation of oceanic crust at sides of submarines zones and ridges of mountains and then tends to spread awayfrom that surface.
Other options are incorrect because tectonic plate movement,sediment deposition measure and global climate variation is not expressed through theory of Harry Hess.Thus, the correct option is option(A).