A revival gathering seems to be a sequence or set of worship services organized in Christianity to encourage committed representatives of such a universal church to encourage young adherents.
Restoring life, awareness, vigor, power, etc. when using, embrace, or currency: reviving ancient traditions.
An evangelistic operation through a collection of activities aimed at bringing about a religious or moral awakening: conducting a revival.
The other given choices are not related to the given instance. So that option B would be the appropriate choice.
