Answer:
C. Both emit hydrogen into the air.
E. Both involve drilling into the earth.
Step-by-step explanation:
Acquiring natural gas and oil have two major affects on environment; that is they both emit hydrogen gas into the air and they both involve drilling into the earth.
Releasing of hydrogen gas into the air have many harmful effects such as it causes increased level of global warming. Another effect on environment for acquiring natural gas and oil is that it involves drilling into the earth. To acquire these natural resources, drilling process is done into the earth's surface.
Therefore, option C and E are correct.