<p>(Just by unplugging your) cell phone charger when you are not using it reduces carbon dioxide pollution.</p>
<p>a.) Just by unplugging your
b.) Just unplugging one's
c.) Just unplugging your
d.) By just unplugging your
e.) If you just unplug your</p>
<p>the answer is C, but im not too sure why A is wrong, and by d and e are wrong either</p>
<p>C is more concise</p>
<p>i think, A is wrong because “by” implies an action on your part, so it should be followed by “you reduce …” instead of “reduces” only</p>
<p>“Just by unplugging” would only work if it were:
Just by unplugging your cell phone charger when you are not using it, you can reduce carbon dioxide polllution</p>
<p>From a solely strategic standpoint C would immediately stand out as the right answer to me. This is because it is almost identical to B, but B has a pronoun shift so it’s clearly wrong. </p>
<p>I hope that makes sense.</p>