OE


Profuse, prolific.

First, examine the structure of the sentence to determine the role of the blank. "The abilities of microorganisms to [do something] are more $\qquad$ than is commonly thought: from [X], to [Y], their innovative capabilities know no end." The blank describes the "abilities." The colon indicates that examples will follow of what is meant by the first part of the sentence. In the idiom "from X , to Y ," the examples X and Y are just two abilities, and the idiom suggests a range of other abilities in between. This is further supported by "their innovative capabilities know no end." Thus, the blank should be a synonym for "unlimited." The synonyms "profuse" and "prolific" mean abundant or plentiful, which fits the desired meaning. "Advantageous" and "beneficial" are synonyms meaning favorable or leading to good results. "Accommodating" forms something of a false triple with the previous pair: it means obliging someone else's wishes and, like "beneficial," is a synonym for helpful. Any of these could describe "abilities," but none of the three address the meaning of the idiom or of capabilities that "know no end." Finally, "ineffectual" means unproductive, so this choice is not only unpaired, it is also nearly opposite the intended meaning.