The biot-savart force law deals specifically with:
a/the magnetic field surrounding a long, straight wire
b/ currents induced in a conductor
c/ the duplication of poles in a bisected bar magnet
d/ the force between magnetic poles

a. the magnetic field surrounding a long, straight wire

Explanation:

The Biot-Savart law was formulated by Jean Baptiste Biot and Felix Savart and describes how a magnetic field is generated by a stationary electric current.

In other words:

The law formulated by Biot and Savart relates the magnetic fields with the currents that create them.

Therefore, the correct option is a.

The magnetic field surrounding a long, straight wire.

a) the magnetic field surrounding a long, straight wire

Explanation:

The Biot-Savart force law states that when an electrical conductor is passed through an electric current, a magnetic field will spontaneously appear around it. A characteristic of this magnetic field is that it is constituted by lines of force that are circular so that we can place compasses at different points at the end of the field and the north of each one will always face the tangential direction of the lines of the field.

This effect was discovered by Hans Christian Oersted, who realized through experiments that a magnetic needle positioned parallel to an electrical conductor would undergo significant deflection in relation to its original position. We can know the direction and direction of the magnetic field generated through the Right Hand Rule and its value at different points through the Biot-Savart Law.

c.is a substance that requires a small amount of energy per gram to raise its temperature; has strong cohesive forces between molecules.

explanation:

a colorless, transparent, odorless liquid that forms the seas, lakes, rivers, and rain and is the basis of the fluids of living organisms.

i don't know that i agree with that but what's the question ?