Humans' emotional tendencies are essentially unchanged from t

Here's my analysis of D vs E

(D) Regardless of the range of choices available to humans, they choose on the basis of their emotions alone.
choices are based on emotions alone is TOO strong. The conclusion will hold even if humans primarily rely on emotions and use logic a bit as well.

(E) Humans would now be able to make wiser choices than in centuries past only if an essential change had taken place in humans' emotional dispositions.
This basically says that to make wiser decisions, human should have evolved emotionally. Notice the tone of the answer.
Negate: If Humans could make wiser choices without growing emotionally, the conclusion falls apart.

Answer: E

when in doubt go for words : the alone in option D gives a red flag there could be other less important factors affecting wise decision
E is not worded strongly and hence the best bet

Got it .. We need not pick any "Too Strong" statements...

without assuming option D.. We cannot go to option E.Humans would now be able to make wiser choices than in centuries past only if an essential change had taken place in humans' emotional dispositions...my question is,where the basis that humans make wise decisions based on emotions.. we can say this only after assuming that humans make decisions on emotions, which is option D. I think option D is correct.

Humans' emotional tendencies are essentially unchanged from those of the earliest members of our species. Accordingly, although technology makes possible a wider range of individual and societal choices than in centuries past, humans are generally unable to choose more wisely.

Summary:

Emotional Tendencies Unchanged
Tech makes wider range of choices now than in the past
Conclusion: Humans are unable to choose more wisely

This is an example of Supporter Assumption since the information in the premise is not found in the conclusion and vice versa.

Logical Chain: Unchanged -> Unable to choose wisely
Contrapositive: Choose wisely -> change


The argument depends on assuming which one of the following?


This is a trap if one is so familiar with Defender question type: Eliminating the error in statistic However, this is not the case in this argument. This choice is a bit extreme because of the word "significant". As long as there is a change, the argument will hold trues whether the change is significant or not. (A) is out.

Do we know that humans make wise choices when they are in control of their emotions? This could be true in real life but not in the context of the argument. (B) is out.

This means: Wiser -> not disposed to heed the lessons of history. Do humans have to learn that or Can they simply changed through evolution? (C) is out

The author does not say nor imply that humans choose bon the basis of their emotions ALONE (D) is out

This states the exact contrapositive discussed above.

(E) is the answer

Tip: whenever you see "if.. then" or "only if.. then" construction in the answer choices, think in terms of such logical implications when evaluating the answer choice.

Let A= unchanged emotional tendencies
B= making wise decisions.

The basic assumption, According to the original argument, is If A -----> NOT B :
that is, IF A (Humans' emotional tendencies are essentially unchanged) ----> NOT B (humans are generally unable to choose more wisely)
So, A ---> (implies) NOT B, is the assumption.

For "ONLY IF" arguments, remember the following:
Given: Only if X ---> Y
Implications:
1) Y ---> X
2) NOT X ---> NOT Y

Look at option E now:
(E) Humans would now be able to make wiser choices than in centuries past only if an essential change had taken place in humans' emotional dispositions.
Basically, option E tells us that: Only if NOT A ---> B
This implies: NOT (NOT A) ----> NOT B; that is, A ----> Not B
That is exactly what our assumption is!
Answer E.

Option E:

Only if change in emotions -> then humans choose wisely = If NO change in emotions -> then humans DON'T choose wisely.

The underlined part is the assumption.

I too got it wrong with D.
Your (and mine) thought process is correct. However, I think you (and me) failed to comprehend that what you are saying is mentioned in option E , convoluted words though.
And D too mentioned the same thing but gone far ahead of the generalization stated in premise (word "ONLY)".

Hope this clarifies.

Humans' emotional tendencies are essentially unchanged from those of the earliest members of our species. Accordingly, although technology makes possible a wider range of individual and societal choices than in centuries past, humans are generally unable to choose more wisely.

The argument depends on assuming which one of the following?

(A) Humans have undergone no significant changes since the origin of the species. - WRONG. Blatantly wrong. Extreme scenario.
(B) Humans who make wise choices are generally in control of their emotions. - WRONG. Controlling is irrelevant.
(C) Human history cannot make humans any wiser unless humans are emotionally disposed to heed the lessons of history. - WRONG. Unless is a bit extreme to say.
(D) Regardless of the range of choices available to humans, they choose on the basis of their emotions alone. - WRONG.
(E) Humans would now be able to make wiser choices than in centuries past only if an essential change had taken place in humans' emotional dispositions - CORRECT.

D and E are contenders here. Chose D sadly .
Missed 'alone' that suggests extreme. Although humans choose with emotions but is it the only one. We aren't sure about it. E, on the other hand, does look like an inference for a moment.

Answer E.
Answer E.