Apostrophe Abuse/neglect

[Spexxvet]

Originally Posted by monster

...
a) Intra-Mural Sports' Teams
b) Intra-Mural Sports Teams
c) Intra-Mural Sport's Teams

It's a title referring to several school teams who play a sport against teams from other schools. The teams are the people doing the fundraising the poster is about, ...

They are teams fundraising for sports. No possessive.

BTW, if they are playing against other schools, they are interscholastic, not intramural.