Select the most appropriate option to substitute the underlined segment in the given sentence. If there is no need to substitute it, select No Improvement.

While there is still a debate about why depression, anxiety and suicide have skyrocketed among people, today, ubiquitous smartphone use plays surely a part.

A

smartphone use surely plays a part

B

smartphone use would surely play a part

C

smartphone usage plays a part surely

D

No Improvement