Greenhouse Gas Emissions Have Been Referred to as a Negative

Greenhouse gas emissions have been referred to as a negative public good because one person's exposure

A) reduces another's, and no one individual can be shielded from its effects.
B) does not reduce another's, and a particular individual can easily be shielded from its effects.
C) reduces another's, and a particular individual can easily be shielded from its effects.
D) does not reduce another's, and no one individual can be shielded from its effects.