Which of the following forces are conservative?

Select all that apply

• Option A

  $\vec{F}$=2r³r̂

• Option B

  $\vec{F}$=-(5/r)r̂

• Option C

  $\vec{F}$=3(xî+yĵ)/(x²+y²)^(3/2)

• Option D

  $\vec{F}$=3(yî+xĵ)/(x²+y²)^(3/2)