Question bonnie

3.1 Boundaries - Coordination vs subordination for clarity
0:00

Bonnie Buratti of NASA’s Jet Propulsion Laboratory blank data about Saturn’s rings collected by the Cassini spacecraft when she made an interesting discovery: the tiny moons embedded between and within Saturn’s rings are shaped by the buildup of ring material on the moons’ surfaces.

Which choice completes the text so that it conforms to the conventions of Standard English?

A.

studies 

B.

has been studying

C.

will study

D.

was studying