This is mostly achieved by the Pronator Teres and hte Pronator Qudratus muscles.
Biceps brachii or supinator. But I can't choose.
supinator
Pronator quadratus and pronator teres perform pronation, brachioradialis aids initiation of the movement.
The pronator teres and pronator quadratus
Pronator teres
The antagonist for the supinator muscle is the pronator teres muscle. These muscles work in opposition to each other to produce rotation of the forearm.
pronates the forearm
Pronator teres
The Pronator Teres muscle pronates the forearm at the radioulnar joint. It also provides flexion of the forearm at the elbow joint
The antagonist for the brachioradialis muscle is the pronator teres. It helps to produce opposite movements at the elbow joint, with the brachioradialis mainly responsible for elbow flexion and the pronator teres for elbow extension.
The most common treatment for pronator teres syndrome, which is often mis-diagnosed as carpal tunnel syndrome, is Neuromuscular Therapy or Trigger Point Therapy to eliminate myofascial trigger points in the pronator teres muscle, and its associated muscles and antagonists like the supinator.
Pronator quadratus and pronator teres
The teres major muscle is considered to be antagonistic to the teres minor muscle. The teres major muscle is a larger muscle located in the upper arm that works to extend, medially rotate, and adduct the arm, while the teres minor muscle is a smaller muscle that works to laterally rotate the arm.
Supinator. Also, as pronator teres also contributes to flexion of the elbow, that action is antagonized by the triceps.