No Clues... Please Help

(A) should be correct. all others are filled with errors.

ronnie1985 wrote:According to a study published by Dr. Myrna Weissman, only one percent of Americans born before 1905 had suffered major depression by the age of seventy-five; of those born since 1955, six percent had become depressed by age twenty-four.
(A) only one percent of Americans born before 1905 had suffered major depression by the age of seventy-five; of those born since 1955, six percent had become depressed by age twenty-four
(B) only one percent of Americans born before 1905 suffer major depression by the age of seventy-five; if they are born since 1955, six percent become depressed by age twenty-four
(C) of Americans born before 1905, only one percent of them have suffered major depression by age seventy-five, but six percent of those born since 1955 do by the age of twenty-four
(D) major depression is suffered by the age of seventy-five by only one percent of Americans born before 1905, and by age twenty-four by the six percent born since 1955
(E) Americans born before 1905 suffer major depression by the age of seventy-five only one percent of the time, but six percent of those born since 1955 did so by age twenty-four

IMO (A)

OA not provided

A - PUBLISHED..HAD SUFFERED...HAD BECOME (sequence of events clear)
B - SUFFER (present tense) is wrong (sentence talks about people suffering in past); use of IF (conditional) incorrect; If we assume IF THEY ARE is correct...then past tense (BECOME) is wrong. With SIMPLE PRESENT CONDITIONAL WE CAN either use SIMPLE PRESENT OR FUTURE

C - HAVE SUFFERED (wrong); many other errors

D - IS SUFFERED

E - SUFFER

IMO A

IMO A

Please use spoilers to OA and IMO

According to a study published by Dr. Myrna Weissman, only one percent of Americans born before 1905 had suffered major depression by the age of seventy-five; of those born since 1955, six percent had become depressed by age twenty-four.

(A) only one percent of Americans born before 1905 had suffered major depression by the age of seventy-five; of those born since 1955, six percent had become depressed by age twenty-four (uses past perfect to correctly convey the sequence)

(B) only one percent of Americans born before 1905 suffer major depression by the age of seventy-five; if they are born since 1955, six percent become depressed by age twenty-four (changes to present tense, ruining the sequence)

(C) of Americans born before 1905, only one percent of them have suffered major depression by age seventy-five, but six percent of those born since 1955 do by the age of twenty-four (changes to present perfect and present, ruining the sequence)

(D) major depression is suffered by the age of seventy-five by only one percent of Americans born before 1905, and by age twenty-four by the six percent born since 1955 (changes to present, ruining the sequence; awkward phrasing)

(E) Americans born before 1905 suffer major depression by the age of seventy-five only one percent of the time, but six percent of those born since 1955 did so by age twenty-four (changes to present and simple past, ruining the sequence)