Correct Answer  Option 3 : Onefourth as of Q
CONCEPT:
Stress (S):
 Stress is the ratio of the load or force to the crosssectional area of the material to which the load is applied.
 The standard unit of stress is N/m.
\(⇒ Stress =\frac{Force(F)}{Area (A)}\)
 When a rod or wire pulled from both sides then the stress generated is tensile stress.

Normal stress: It is the restoring force per unit area perpendicular to the surface of the body.

Tangential stress: When the elastic restoring force or a deforming force acts parallel to the surface area, the stress is called tangential stress.
EXPLAINATION:
Given  Force of wire P = Force on wire Q and Radius of P (r_{p}) = 2r_{Q}
 From the above, it is clear that stress is written as:
\(⇒ Stress =\frac{Force(F)}{Area (A)}\)
 Since stress is inversely proportional to the area, and the area is proportional to the square of the radius. Therefore, stress is the directly proportional square of the radius.
 Now the ratio of the stress of both wire can be expressed as:
 Stress for wire P is,
\(⇒ S_P=\frac{Force}{\pi r^2_{P}} = \frac{Force}{4\pi r^2_{Q}} \)  (1)
\(⇒ S_Q=\frac{Force}{\pi r^2_{Q}}\)  (2)
On diving equation 1 and 2, we get
\(⇒ \frac{S_P}{S_Q}=\frac{1}{4}\)
\(\Rightarrow S_P=\frac{1}{4}\times S_Q\)
 Therefore, stress on P is onefourth the stress on Q. Hence, The correct option is (3)