Although amyotrophic lateral sclerosis, or ALS

[sw001]

Although amyotrophic lateral sclerosis, or ALS, typically causes death within 3 to 5 years of the onset of symptoms, on average, the famous physicist Stephen Hawking has defied the odds, in contrast, by living more than 40 years after his initial diagnosis.

A. typically causes death within 3 to 5 years of the onset of symptoms, on average, the famous physicist Stephen Hawking has defied the odds, in contrast,
B. causes death within 3 to 5 years of the onset of symptoms, on average, the famous physicist Stephen Hawking has defied the odds, in contrast,
C. typically causes death within 3 to 5 years of the onset of symptoms, the famous physicist Stephen Hawking has defied the odds
D. causes death within 3 to 5 years of the average onset of symptoms, the famous physicist Stephen Hawking has defied the odds, by contrast,
E. typically causes death within 3 to 5 years of the average onset of symptoms, the famous physicist Stephen Hawking has defied the odds


1. Option E - I understand that "on average" and "typically" are redundant. But, in option E, average is used with a different meaning and reference.

2. Plus, the official explanation - that average could refer to the world average, is not very convincing. Because, average could refer to average of when the person's symtoms start to show up, could be span of 2 months, 6 months. And, every person with ALS would start to show symtoms at different ages)

3. In addition, I feel it makes more sense to have on average there, because later also we are referencing 3 - 5 years.

[RonPurewal]

1. Option E - I understand that "on average" and "typically" are redundant. But, in option E, average is used with a different meaning and reference.

yes—specifically, it's used with a meaning that is nonsense.

"the average onset of symptoms" -- this doesn't have any reasonable meaning.
the "onset of symptoms" is a precise occurrence; we're talking about average time spans after that onset.

[RonPurewal]

3. In addition, I feel it makes more sense to have on average there, because later also we are referencing 3 - 5 years.

ironically, this is another reason why "average" doesn't make sense.

an "average" is a single figure. a range of figures—e.g., 3 to 5 years—is not an average.
on the other hand, if that range contains some sizable portion (probably a majority) of instances, then we can say that things typically fall within that range.