Final answer:
In the framing of a vent opening in a gable end, the space between the header and sill is filled by cripple studs. Cripple studs are essential in the structure's load transference, combining with king and jack studs to properly support the frame around openings.
Step-by-step explanation:
The vent opening in a gable end is framed using a header, a sill, and cripple studs. When constructing window openings or vents in a gable end, a header spans the top of the opening providing structural support, whereas a sill forms the bottom. The gap between the header and sill is filled with vertically oriented cripple studs, which are shorter studs cut to fit the space. Cripple studs are essential in transferring loads around the opening to the king studs and into the structure's framing. These king studs run continuously from the top to the bottom of the wall framing, flanking the sides of the opening. The option 'b' which is jack studs, are also involved in the framing process. Jack studs provide support directly underneath the header and run from the bottom sill or sole plate to the underside of the header.