In 1992 outlaw fishing boats began illegally harvesting lobsters from the territorial waters
of the country of Belukia. Soon after, the annual tonnage of lobster legally harvested in
Belukian waters began declining; in 1996, despite there being no reduction in the level of
legal lobster fishing activity, the local catch was 9,000 tons below pre-1992 levels. It is
therefore highly likely that the outlaw fishing boats harvested about 9,000 tons of lobster
illegally that year.
Which of the following is an assumption on which the argument depends?
A. The illegal lobster harvesting was not so extensive that the population of
catchable lobsters in Belukia’s territorial waters had sharply declined by 1996.
B. The average annual lobster catch, in tons, of an outlaw fishing boat has increased
steadily since 1992.
C. Outlaw fishing boats do not, as a group, harvest more lobsters than do licensed
D. The annual legal lobster harvest in Belukia in 1996 was not significantly less than
E. A significant proportion of Belukia’s operators of licensed lobster-fishing boats
went out of business between 1992 and 1996.
I think A. It must be assumed that the population is still sizable.
Let's say pre 1992 level was 18000 for legal harvesters. Now in 1996 legally 9000 would be caught. This does not mean that the remaining 9000 was caught illegally unless it is assumed that the number of catchable lobsters have not come down. Otherwise if lets say teh catchable lobster is only 13000 in 1996 then if 9000 were harvested legally (less 9000 of pre 1992 level) - the illegal folks can only capture as much as 4000.