|Question 16Verbal

Source Texts

Text
A recipient of both the Wolf Prize in Chemistry and the Robert A. Welch Award, chemist Ahmed Zewail expanded the limits of measurability when he devised a novel technique in optical spectroscopy that allows researchers        chemical reactions occurring within molecules around a quadrillionth of a second, or one femtosecond.
Which choice completes the text so that it conforms to the conventions of Standard English?
to study
A
will study
B
who study
C
studying
D