Characters who play tricks called tricksters often show up in native american stories.

what is missing from this sentence to make it clearer?
a.
a comma after the word "tricks"
b.
a comma after the word "tricksters"
c.
commas around the phrase "called tricksters"
d.
nothing is missing; the sentence is correct

the correct answer is the following.

one of the groups i belong to is the boy scouts. this is a problem-solving group because it has tasks that we need to solve in order to other people in different activities such as the rescue of lost pets, or elder people in need.

the other group i belong to is kids pro environment, and is an information-sharing group that tries to create conscience about the risks and problems that generate pollution in our cities. we share information to other students and parents on the importance of keep our communities clean and our skies clear.