Comprehending the argument

According to the video, which one of the following reasons explains that social relationships are powerful influences on our habit formation?

(Choice A)
Knowing we’re being observed makes us feel accountable to our own principles and goals.
(Choice B)
Relationships motivate us to work hard to impress people, thus improving our social status.
(Choice C)
People with strong social relationships are at lower risk of depression and anxiety.
(Choice D)
Friendships of virtue require genuine care and concern for each other.

Wireless Philosophy