Below is part of the abstract of a research articl...
Below is part of the abstract of a research article. Which sentence identifies the problem with previous studies? (1) In widgetology, it's long been understood that you have to glomp the widgets before you can squiffle them. (2) However, there is still no known general method to determine when they’ve been sufficiently glomped. (3) This paper introduces a new glomping technique, called googa-glomping, which allows direct measurement of whifflization, a superior metric for assessing squiffle-readiness. (4) We describe a series of experiments on each of the five major types of widget, and show that in each case, googa-glomping runs faster than competing techniques, and produces glomped widgets that are perfect for squiffling.
A、Sentence 1
B、Sentence 2
C、Sentence 3
D、Sentence 4