This is a matching-type question where we need to analyze four different configurations of current-carrying wires and match them with the resulting effects at a point P or on the wires themselves.

Analysis of Configuration (A)

1. Diagram Description: Two long, parallel, straight wires are shown. One carries current I out of the page (represented by a dot), and the other carries current I into the page (represented by a cross). Point P is situated midway between them.
2. Magnetic Field at P: We use the right-hand thumb rule to find the direction of the magnetic field from each wire at point P.
   • For the wire with current coming out of the page, the magnetic field at P is directed downwards.
   • For the wire with current going into the page, the magnetic field at P is also directed downwards.
   • Therefore, the magnetic fields at P from both wires are in the same direction. This corresponds to statement (P).
   • Since both fields are in the same direction and are non-zero, the net magnetic field at P is non-zero. This means statement (R) is incorrect.
3. Interaction: Wires carrying currents in opposite directions repel each other. This corresponds to statement (S).
4. Initial Conclusion for (A): The correct matches for configuration (A) as depicted are (P) and (S).

Re-evaluation based on Options

None of the provided options match A with (P) or (S) without also incorrectly matching it with (R). For example, option A is A -> (P, R), but we found R to be incorrect. All options list (R) as a match for either (A) or (C). Let's re-examine.

It is highly probable that there is a typo in the diagram for configuration (A) and the currents are intended to be in the same direction (e.g., both out of the page).

Analysis assuming typo in (A) (currents in same direction)

1. Magnetic Field at P:
   • For the left wire (current out), the field at P is downwards.
   • For the right wire (current out), the field at P is upwards.
   • The fields are in opposite directions. This corresponds to statement (Q).
   • Since P is midway, the distance to each wire is the same. The currents are also the same. Therefore, the magnitudes of the magnetic fields are equal.
   • With equal magnitudes and opposite directions, the net magnetic field at P is zero. This corresponds to statement (R).
2. Conclusion for (A) with typo: A → (Q, R).

Analysis of Configuration (B)

1. Diagram Description: Two coaxial circular wires of the same radius carry current I in the same direction. P is the midpoint of the line joining their centers.
2. Magnetic Field at P: Using the right-hand rule for circular loops, the magnetic field on the axis points along the axis.
   • For the left coil, the field at P is directed to the right.
   • For the right coil, the field at P is also directed to the right.
   • The magnetic fields at P are in the same direction. This corresponds to statement (P).
3. Conclusion for (B): B → (P).

Analysis of Configuration (C)

1. Diagram Description: Two coaxial circular wires of the same radius carry current I in opposite directions. P is the midpoint of the line joining their centers.
2. Magnetic Field at P:
   • For the left coil, the field at P is directed to the right.
   • For the right coil (current reversed), the field at P is directed to the left.
   • The magnetic fields at P are in opposite directions. This corresponds to statement (Q).
   • Since the coils have the same radii, carry the same current, and P is equidistant from their centers, the magnitudes of the fields are equal.
   • Therefore, the net magnetic field at P is zero. This corresponds to statement (R).
3. Conclusion for (C): C → (Q, R).

Analysis of Configuration (D)

1. Diagram Description: Two concentric, coplanar circular wires. The inner wire has current I clockwise, and the outer wire has current I counter-clockwise. P is the common center.
2. Magnetic Field at P: The magnetic field at the center of a circular loop of radius r is B = μ₀I / (2r).
   • For the inner loop (radius r₁, clockwise current), the field B₁ is into the page.
   • For the outer loop (radius r₂, counter-clockwise current), the field B₂ is out of the page.
   • The magnetic fields at P are in opposite directions. This corresponds to statement (Q).
   • Since r₁ < r₂, the magnitudes are different: |B₁| = μ₀I / (2r₁) > |B₂| = μ₀I / (2r₂). The net field is non-zero, so (R) does not match.
3. Conclusion for (D): D → (Q).

Final Matching

Based on the analysis (including the correction for the likely typo in A):

• A → (Q, R)
• B → (P)
• C → (Q, R)
• D → (Q)

This combination matches option B.