Twenty years ago the Republic of Rosinia produced nearly 100 million

hi,

im confused with this :
i know that the assumption is a new piece of information (so it can not be a rephrasing to a premise or conclusion)
answer B "Strains of potatoes most commonly grown in Rosinia could not have produced the yieldslast year that they once did" is a rephrasing to the premise (but last year the harvest barely reached 60 million tons). in the premise we can see that last year the production is less than it used to be.
so, how can answer B an assumption ??? it is more an inference than an assumption .
can any one explain that please ?

thanks

Premise - harvest decreased last year
Conclusion - decrease is a result of no new higher-yeilding strains of potatoes are developed
Assumption - New higher-yielding strains are necessary to increase the harvest, OR, the older strain is not sufficient to increase the harvest

Also try negating B ->
B) Strains of potatoes most commonly grown in Rosinia could not have produced the yields last year that they once did.
Negating B -> Strains of potatoes most commonly grown in Rosinia COULD HAVE produced the yields last year that they once did - which means the reason for a decrease in harvest is something else and not the inability of agricultural researchers to produce new higher yielding strains. This completely weakens the conclusions and hence B) has to be the correct assumption, without it the argument falls apart.

Negation really works well in assumption questions. I have only started trying it and it does wonders. I would suggest this technique to anyone facing issues with assumption. It will take long initially but over time you will become quick at it.

Hope this helps.

The structure of the sentence is - Premise + missing premise (or assumption) - conclusion.

So if the missing premise is given, the conclusion will be more solid.

Also there is no direct link between the given premise and conclusion, so the missing premise has to fill this void.

Now let's look at option B : Strains of potatoes most commonly grown in Rosinia could not have produced the yieldslast year that they once did.

Now let's use negation technique and let's see whether conclusion holds or not.

Negating option B : Strains of potatoes most commonly grown in Rosinia could have produced the yieldslast year that they once did.

So after negating the option B, the conclusion does not hold, so option is the missing premise/assumption required by the argument.

Twenty years ago the Republic of Rosinia produced nearly 100 million tons of potatoes, but last year the harvest barely reached 60 million tons. Agricultural researchers, who have failed to develop new higher-yielding strains of potatoes, are to blame for this decrease, since they have been concerned only with their own research and not with the needs of Rosinia.

Which one of the following is an assumption on which the argument depends?

(A) Any current attempts by agricultural researchers to develop higher-yielding potato strains are futile. - WRONG. Supports the conclusion rather.

(B) Strains of potatoes most commonly grown in Rosinia could not have produced the yieldslast year that they once did. - CORRECT. If that had been possible then blaming researchers makes sense.

(C) Agricultural researchers often find concrete solutions to practical problems when investigating seemingly unrelated questions. - WRONG. Again irrelevant.

(D) Wide fluctuations in the size of the potato crop over a twenty-year period are not unusual. - WRONG. 2nd best but doesn't impact the conclusion. Even if they are usual then the conclusion still holds anyway.

(E) Agricultural research in Rosinia is funded by government grants. - WRONG. Irrelevant.

Answer B.

Type: Argument
Conclusion: Agricultural researchers, who have failed to develop new higher-yielding strains of potatoes, are to blame for this decrease
Premise 1: Decreased harvest
Premise 2: Concerned only with their own research
Assumption: New higher-yielding strains of potatoes is necessary
Answer: (B) Strains of potatoes most commonly grown in Rosinia could not have produced the yields last year that they once did.