The pelvic floor is formed by Levator ani along with which muscle?

• A. Piriformis
• B. Psoas major
• C. Iliopsoas
• D. Obturator internus

Answer: (A)

The pelvic floor, or pelvic diaphragm, is formed by the levator ani together with the coccygeus muscle. The levator ani provides the main support for pelvic organs, while the coccygeus supports the posterior aspect and anchors to the coccyx. The other muscles listed are located in the pelvis but do not constitute the pelvic floor: piriformis lies on the posterior pelvic wall and helps form part of the boundary of the greater sciatic foramen; psoas major and iliopsoas are primarily hip flexors that cross the pelvic brim; obturator internus forms part of the lateral pelvic wall and the pudendal canal. Thus, the classic pairing for the pelvic floor is levator ani with coccygeus; none of the listed options truly completes that group, though piriformis is the closest pelvic-region muscle in terms of location, it is not a component of the pelvic floor.