A surgeon entering the abdominal cavity through the abdominal wall will take care to avoid injury to the vessels and nerves within the wall. The main poion of these vessels and nerves will be found immediately deep to which of the following

The main course of the intercostal vessels and nerves is deep to the internal abdominal oblique muscle in the neurovascular plane. The anterior abdominal wall is composed of three paired flat muscles that, in general, arise from bony structures posteriorly and whose fibrous aponeuroses form the rectus sheath and meet to form the linea alba.These muscles are from superficial to deep: the external abdominal oblique, internal abdominal oblique, and transversus abdominis. These muscles are supplied by segmental branches of the thoracic and abdominal aoa: the 10th, 11th, and 12th (subcostal) intercostal aeries and the 1st or 2nd lumbar aeries. These aeries, their companion veins, and the nerves supplying the muscles are all found in the interval between the internal abdominal oblique and the transversus abdominis muscles, known as the neurovascular plane. Ref:- BD Chaurasia