Asap, 4 choices

which sentence states a bias held by the author of the article?

a. u. s. paleontologists say they have discovered fossils of the largest-known dinosaur ever to roam north america, whose size rivals that of long-necked dinosaurs from south america.

b. the new study by researchers is published in the journal, acta palaeontologica polonica.

c. all dinosaurs became extinct 65 million years ago.

d. the scientists who conducted the research are with the montana state university museum of the rockies, and the state museum of pennsylvania.