Which statement best explains why this extrusive volcanic rock does not have visible crystals? A. It is homogeneous and composed of a soft mineral.

B. It does not contain atoms of any Earth minerals.

C. It cooled down before large crystals could form.

D. It wasn’t exposed to friction during its formation.

Sarah and john are having a discussion on genetic diversity. sarah believes that it happen over a long period of time. john it happens immediately. who is correct? a. sarah is correct because genetic diversity occurs over a long period of time. b. john is correct because genetic diversity occurs immediately. c. both are correct because genetic variation can occur or long period of time. d. neither are correct because genetic diversity occurs over any period of time