Question

drag the missing word into place
then, well describe how a mineral breaks.
if its smooth, flat and with no mistakes,
it has!
hardness
streak
cleavage

Explanation:

Cleavage refers to the way a mineral breaks along smooth, flat planes. Hardness is a measure of a mineral's resistance to scratching. Streak is the color of a mineral in powdered form. Since the description is about how a mineral breaks (smooth, flat), it matches the definition of cleavage.

Answer:

cleavage