Given: Three #14 AWG two-conductor with ground type NM cables are spliced in a metal octagonal junction box that has cable clamps and a cover. What is the minimum trade size box that may be used? (2 x 3 +1+1)

Given: Three #14 AWG two-conductor with ground type NM cables are spliced in a metal octagonal junction box that has cable clamps and a cover. What is the minimum trade size box that may be used? (2 x 3 +1+1)