As a behavioral economist, Francesca Gino of Harvard Business School examines human economic behavior through a lens that, _____ elements of psychology and economics, illuminates how and why (and to what effect) people make particular choices.
Which choice completes the text so that it conforms to the conventions of Standard English?
Explanation
Context: The main clause "Francesca Gino...examines human economic behavior through a lens that, __ elements of psychology and economics, illuminates" — the blank modifies "a lens." The main verb "illuminates" is already present.
Answer: C) combining
Why? "Combining elements of psychology and economics" is a participial phrase modifying "a lens." The -ing form is needed as a modifier, not a finite verb.
Traps:
- A) combines → finite present; creates a run-on inside the relative clause
- B) combine → plural finite; wrong number and creates a run-on
- D) is combining → finite progressive; creates a run-on