In DNA, the sides of the ladder consist of alternating segments of phosphate and

According to Freud, little boys cope with the guilt of wanting to kill their fathers by

wanting to kill themselves. identifying with their father. becoming angry with their father. becoming envious of their father's penis.

Which of the following types of prevention tends to be the most difficult because it involves large-scale societal changes?

A. quaternary B. tertiary C. primary D. secondary