Explanation
$$\textbf{Hint}$$ Apply newton's second law of motion.
STEP (1): SI Unit
Force acting on the body may affect the shape of the body or it will accelerate or decelerate the body, or it will give motion to the static body or it will stop the motion of the dynamic body.
$$F = ma$$
Where $$'F'$$ = force applied, $$'m'$$ = mass and $$'a'$$ = acceleration
Acceleration $$a = \dfrac vt$$
Where $$v$$ = velocity (in m/s)
Here $$'m'$$ is mass and $$'s'$$ is seconds
Time $$'t'$$ is in seconds
Therefore acceleration unit is = $$\dfrac{\dfrac ms}s = \dfrac m{s^2}$$
Hence unit of force = $$kg \dfrac m{s^2} = Newton$$ (in S.I. unit) i.e, option $$D$$ is a unit of force
Newton can converted into Pound
that is 1 Newton = 0.22481 pound ( in FPS system ) i.e, option $$A $$ is unit of force
$$\textbf{Step2:CGS Unit}$$
$$F = \dfrac{g.cm}{s^2} = Dyne$$ (in C.G.S. unit) i.e, option $$ B $$ is a unit of force
Here $$'g'$$ is grams , $$'cm'$$ is centimeters and $$'s'$$ is seconds
Conclusion: Joule is the correct answer because it is the unit of energy.
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