data have shown that people who get more early in the day have lower bmis.

The answer is light exposure. Individuals who get more exposed in light early in the morning are believed to have lower BMIs than those who don’t. Individuals who immerse themselves to intense light for almost or at least half an hour have possible lowered BMIs than others, individuals who also avoid exposure to light at night may also contribute to prime health and proper weight control.

it should be d or b but i'm sure it's d