A study led by scientist Rebecca Kirby at the University of Wisconsin-Madison found that black bears that eat human food before hibernation have increased levels of a rare carbon isotope, ________, due to the higher C levels in corn and cane sugar. Bears with these elevated levels were also found to have much shorter hibernation periods on average.
MM
Mashaal Masha
Jan 06, 2024
A study led by scientist Rebecca Kirby at the University of Wisconsin-Madison found that black bears that eat human food before hibernation have increased levels of a rare carbon isotope, ________ due to the higher $^{13}C$ levels in corn and cane sugar. Bears with these elevated levels were also found to have much shorter hibernation periods on average.
Which choice completes the text so that it conforms to the conventions of Standard English?