What should be true of a molecule being used as a molecular clock? . a)it has a consistent rate of neutral mutations from generation to generation.. b)it is a rare molecule that is not found in many living species that might be compared.. c)its mutations always affect the phenotype, making it easier to observe the changes.. d)it serves an unnecessary function, making it less likely to be preserved over time.

Subduction zones form when an oceanic plate collides with another oceanic plate or continental plate. the continental crust is lighter and less dense than oceanic crust. continental crust's density is approximately 2.7 grams per cubic centimeter. oceanic crust is thinner and the average density is about 3.3 cubic centimeters. when the two crustal plates converge the oceanic plate always bends and subducts beneath a continental plate. once the oceanic crust subjects, the rocks are subjected to changes in heat and pressure. because of this, we would expect to find rocks in the area of a subduction. a) clastic b) igneous c) metamorphic d) sedimentary