17. Biologists have hypothesized that echinoderms are closely related to chordates because both groups are deuterostomes.

The answer would be true

Deuterostomes are superphylum of Animalia kingdom in taxonomy. The word means the second mouth in the Greek language which characterizes this group with an anus, opening on the other sides of the mouth to dump waste. The member of this superphylum is Chordata, Hemichordata, and Echinodermata.