A prime mover of thigh flexion is the a. rectus femoris, b. iliopsoas, c. vastus muscles, d. gluteus maximus.

Video transcript

Hi, everyone. Let's take a look at this practice problem together, which of the following muscles is located in the ear and responsible for stabilizing the stapes bone, which is one of the three small bones in the middle ear. The answer options are a stus muscle, B, skele muscles, C gluteus, maximus, and D subscapularis. So let's start off with a commonly known muscle, the gluteus maximus. So this is a muscle in the buttock and it's the main hip extensor. So that means we can go ahead and eliminate. Option C. It is not located in the air. Now, option D the subscapularis, if we break down, the name, sub means below and scapula means wing bone. So the sca subscapularis is located on the anterior side of the scapula and it's one of the four rotator cuff muscles in the shoulder. It's not located in the ear, so we can eliminate option D as well. Now, option B, the ski lean muscles, these muscles are three pairs that are located in the deep neck. So there's the anterior, the middle and the posterior. So option B is also incorrect. Now, the Sted muscle option A, this is the smallest muscle in the body. It's the muscle that is located in the ear and it stabilizes that steep B's bone. So the correct answer is option a stapes muscle. All right, everyone. I hope you found this helpful and I'll see you soon for the next practice problem.