Look at each pair of statements. each statement in the pair is labeled as a cause or as an effect. mark the pair of statements if they are correctly labeled.

a.
cause: europe's population decreased.
effect: the black death attacked europe.

b.
cause: there were fewer workers.
effect: peasants left their manors.

c.
cause: the manor system crumbled.
effect: peasant farmers prospered.

d.
cause: cities showed signs of new life.
effect: skilled craftsmen and others moved away from manors.