A scientist is studying a volcano. She claims
that the lava that comes out of the volcano is a
liquid. She wants to make an argument to
support her claim. What question should she
ask to help her collect evidence for her
argument?

A. Does the lava have a definite volume?
B. Is the lava made of particles that move
around?
C. Does the lava have a definite volume and
does it flow freely?
D. Does the lava have a definite volume and
particles that are very far apart?