MM
Mashaal Masha
Jan 09, 2024
In 2015, a team led by materials scientists Anirudha Sumant and Diana Berman succeeded in reducing the coefficient of friction (COF) between two surfaces to the lowest possible level--superlubricity. A nearly frictionless (and, as its name suggests, extremely slippery) state, ________

Which choice completes the text so that it conforms to the conventions of Standard English?
Difficulty: Hard
A:

when their COF drops below 0.01, two surfaces reach superlubricity.

B:

two surfaces, when their COF drops below 0.01, reach superlubricity.

C:

reaching superlubricity occurs when two surfaces' COF drops below 0.01.

D:

superlubricity is reached when two surfaces' COF drops below 0.01.

ID: 659d9c89161c1373e8b83939