Scientists once believed that the oversized head, long hind legs, and tiny forelimbs that characterized Tyrannosaurus...

ali on August 30 at 01:26AM

help

can you explain to as why the answer is b?

1 Reply

Irina on August 30 at 04:12PM

@ali,

Let's look at the argument.

The passage starts off with a hypothesis that certain features of T-rex developed to accommodate the great size and weight of this predator. The passage then cites the evidence of a recently discovered earlier dinosaur skeleton with the same features but one-fifth the size and one-hundredth of T-rex weight, i.e. a mini T-rex version, to conclude that this hypothesis is wrong.

What information do we need to conclude that the argument follows logically?

Let's think about it. The skeleton belonged to an earlier dinosaur - not T-rex - and the author concludes that because it had the same features but no need to accommodate the great size and weight, there must be an alternative explanation for these physical characteristics that this skeleton and T-rex share. (B) makes us question this assumption by asking "At what stage of life did the recently discovered specimen die?" If this is a juvenile dinosaur that failed to reach its adult size and weight, the hypothesis that these physical characteristics developed to accommodate greater weight and height could still hold true. We thus need this additional information to determine if this new evidence is sufficient to refute the T-rex hypothesis.

Does this make sense?

Let me know if you have any further questions.