3、Early in this cengtury Alfred Wegener developed the concept of continental drift。His ideas were rejected vehemently because he postulated no identifiable force strong enough to make the continents move。 we have pinpointed such a force， but because new instruments have finally allowed continetal movement to be confirmed by observation。
（E） when the events a theory postulates are detected， the theory is accepted even without an explanation of how those events are brought about。
3、In 1860 Bavarian quarry workers discovered the impression of a feather in a limestone slab dating to the Mesozoic era。It had previously been assumed that birds developed only after the disappearance of pterosaurs， a species characteristic of that era。 but there in limestone lay the imprint of a fully aerodynamic，three-inch-long feather。 This， therefore， must have been the earliest bird-certainly， the earliest found to that date。
3. A certain stain of bacteria was found in the stomachs of ulcer patients. A medical researcher with no history of ulcers inadvertently ingested some of the bacteria and within weeks developed an ulcer. Therefore, it is highly likely that the bacteria strain induces ulcers.
Which one of the following, if true, most supports the argument above?
