You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Subclan aery is divided by which muscle ? and explain in detail?
Ans. is 'c' i.e., Scaleneus anterior Scaleneus anterior muscle divides subclan aery into three pas :?A) First pa :This pa is medial (proximal) to scaleneus anterior. Branches from first pa are :?Veebral aeryInternal thoracic aeryThyrocervical trunk:Costocervical trunk (on left side only).B) Second pa :This pa lies posterior to scalenus anterior. It gives origin to Costocervical trunk on right side. Costocervical trunk gives following branches:Deep cervical aerysuperior intercostal aery.C) Third pa :This pa lies lateral (distal) to scalenus anterior. It gives dorsal scapular aery (sometimes dorsal scapular aery arises from transverse cervical aery, a branch of thyrocervical trunk).