According to a study published by Dr. Myrna Weissman,

A for me as well
B) destroys the parallellism: "only one percent of Americans ... if they are born since 1955..."
C) in C, "of Americans born before 1905, only one percent of them" The red portion is redundant
D) double use of "by" makes it grammatically unclear as to who suffers depression.
E) changes the meaning of the sentence to "all Americans born before 1905 suffer depression by age 75 one percent of the time". This illogically compares to only "6% of those born since 1955 who suffer depression by age 24 one percent of the time" In a comparison, we have to set AT LEAST one constant. The comparison is wrong here because what about those other 94% of those born since 1955? Do those maybe suffer a major depression by age 75? Hence, how to compare "all Americans born before 1905" to only "6% of those born since 1955"? A valid comparison ground might be to compare the likelihood of those born after 1955 to have a major depression by age 75(same constant in both scenarios). Then, the number of Americans likely to have a heart attack by age 75 would be MUCH GREATER than only 6% and we could therefore ascertain the comparison to be valid

Paul's art of converting SC to CR. :computer