Which of the Following Best Matches the Description

Multiple Choice

Which of the following best matches the description?
-Naturally occurring substances that can be extracted under current conditions.

A) underground mining
B) resources
C) active solar system
D) photovoltaic cell
E) surface mining
F) acid mine drainage
G) geothermal energy
H) secondary recovery
I) resources.
J) liquefied natural gas
K) black lung disease
L) nonrenewable energy sources
M) reserves
N) renewable energy sources
O) passive solar system
P) overburden