Normally, mutations in genetic material occur spontaneously, without a known cause. a genetic disorder is present in approximately of all live births in the united states.

i believe the answer would be b. hope it : )

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.