In wall framing, studs for bottom plates must have full bearing on a _____ inch thick or larger plate or sill having a width at least equal to the width of the studs.

The correct answer is that for wall framing, studs for bottom plates must have full bearing on a 2-inch thick or larger plate or sill, with a width at least equal to the width of the studs. This requirement ensures structural integrity and stability. The 2-inch thickness provides sufficient support to safely distribute the load of the wall above and maintain the alignment of the framing.

A 2-inch thick plate efficiently engages the studs, helping to avoid any potential sagging or misalignment over time that could occur if the bearing surface were inadequate. Moreover, this specification aligns with common building practices and codes that are designed to enhance the strength and durability of wall assemblies.

The other options refer to thicker plates or sills, which are not necessary for the standard requirements for bottom plates in wall framing. While thicker materials may provide additional strength, the minimum requirement is clearly defined as 2 inches, which is deemed sufficient to support the weight of standard framing practices while adhering to safety standards.