D.) Is the most sensible answer.
Explanation: I used the process of elimination to solve this. Groundwater recharge sounds too far off of the topic, snow melt is...well...melting snow, infiltration also has nothing to do with the subject, but surface runoff is the only one that makes sense, is on topic, and seems to have a meaning similar to the occurrences describes in your question.
The fossil record provides evidence of Earth’s changes over time. It's a record keeper of the Earth'd changes over time.
I would say it may generate harmful emissions
Methane the most, small amount of oxygen and other gases
