The average size of marine life that washes up on the shore of the Jap

Official Explanation

Answer: (B)

The argument assumes that what holds true for marine animals in general holds true for giant squids. In other words, it takes a general rule and applies it to a specific case. Just because larger sea creatures in general tend to wash ashore in Australia than in Japan does not mean that the giant squids washed ashore in Australia are larger, on average, than those washed ashore in Japan. This points best to (B).

(A) is wrong because even if the argument had focused on the different sizes of squid (diminutive variants = small squids), it still makes the mistaken assumption that what holds true in general holds true in the case of the giant squid.

(C) is tempting. The argument, however, focuses on the average size of life washed ashore in Japan vs. Australia. Even if the largest giant squid ever seen was found off the shores of Japan, the average size of squids in Japan could still be smaller than that found in Australia. Think of it this way: the average size of squid could be 32 ft long in Japan and 34 ft long in Australia. It doesn't matter that a 44-foot squid--the longest ever--was found in Japan. The problem with the argument is that nothing definitive can be said about the average size of squid in Australia and Japan based on the general observation that aquatic life washed ashore tends to be larger in Australia.

(D), while tempting, reverses the order of things. The paragraph itself takes a general case (sea life in Japan vs. sea life in Australia) and applies it to a specific case (giant squids in Japan vs. those in Australia). The paragraph does not take a specific case and generalize from that case - this is what (D) implies.

(E) is similar to (A) in that it focuses on the difference in size of squids, a fact that doesn't affect the argument. The argument is only focused on giant squids and what you can say about their size based on a general observation on aquatic life washed ashore in either Japan or Australia.