Which muscle is deeper in the body: the internal oblique muscle or the transverse abdominal muscle?

Transverse abdominal muscle

Explanation:

Both internal oblique muscle and transverse abdominal muscles are muscles of abdominal wall and are present in pairs. The fascicles of the internal oblique muscle extend towards those of external oblique muscles. Therefore, the internal oblique muscle is closer to skin.

Transverse abdominal muscle is deep muscle of abdominal wall. Its fascicles are arranged around the abdominal wall. This makes it deeper than internal oblique muscle.