Final answer:
The hip flexors, primarily the pectineus and adductor longus, are responsible for flexing the thigh at the hip joint and are located in the anterior part of the hip and thigh.
Step-by-step explanation:
The hip flexors are a group of muscles that are primarily responsible for flexing the thigh at the hip joint. They are located in the anterior region of the hip and thigh. Among these muscles, the pectineus and adductor longus are notable for their role in adducting and flexing the femur at the hip. The pectineus is situated within the femoral triangle, which lies at the junction between the hip and the leg, and also houses the femoral nerve, femoral artery, femoral vein, and deep inguinal lymph nodes. The adductor muscles, including the adductor longus, adductor brevis, and adductor magnus, medially and laterally rotate the thigh based on the position of the foot. Additionally, the adductor longus assists in thigh flexion and the adductor magnus in thigh extension.