Question

The first arthropods thought to exist are called the _______.
A. arachnids
B. chitin
C. nymphs
D. trilobites

Answer 1

@musa19965 what you think???

Answer 2

I think it is Trilobites

Answer 3

I think its B

Answer 4

its D . http://en.wikipedia.org/wiki/Trilobite
^^

Answer 5

its not B because Chitin is a tough, protective, semitransparent substance, primarily a nitrogen-containing polysaccharide, forming the principal component of arthropod exoskeletons and the cell walls of certain fungi.

Answer 6

oh