Can anyone please help me with this?
Please help me.

Which set of characteristics best describes igneous rock? a) largest type of rock, made of organic matter, hardest type of rock b) least abundant type of rock, made of other rocks, made mostly of minerals c) found on all continents, contains wavy bands of stripes, contains fossils d) most abundant type in earth's crust, made of magma/lava, contains no fossils

This classification of drug typically changes the brain's chemistry and reduces its ability to create its own endorphins.

The identities of substances are the same before and after which type of change