Wanda Diaz-Merced is an astrophysicist who lost her sight when she was young. Diaz-Merced’s condition inspired her to
develop software that can translate scientiﬁc data into sound. Sound-based tools ______ scientists to detect subtle patterns
in data. Such patterns may not be evident in traditional graphs.
has enabled
enable
is enabling
enables
Choice B is the best answer. The convention being tested is subject-verb agreement. The plural verb "enable" agrees in
number with the plural subject "sound-based tools."
Choice A is incorrect because the singular verb "has enabled" doesn’t agree in number with the plural subject "sound-based
tools." Choice C is incorrect because the singular verb "is enabling" doesn’t agree in number with the plural subject "sound-
based tools." Choice D is incorrect because the singular verb "enables" doesn’t agree in number with the plural subject
"sound-based tools."