Which choice completes the text so that it conforms to the conventions of Standard English?
A
has enabled
B
enable
C
is enabling
D
enables
Explanation
Correct answer: B.
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."
Why the other choices are wrong
Choice A
Choice A is incorrect because the singular verb "has enabled" doesn’t agree in number with the plural subject "sound-based tools."
Choice C
Choice C is incorrect because the singular verb "is enabling" doesn’t agree in number with the plural subject "sound-based tools."
Choice D
Choice D is incorrect because the singular verb "enables" doesn’t agree in number with the plural subject "sound-based tools."