1. The problem statement, all variables and given/known data 2. Relevant equations W=-ΔU for conservative force. 3. The attempt at a solution Let all three forces be conservative. Since particle comes back to where it was, ΔU=0. Hence ΔUAB+ΔUBC+ΔUCA=0 Hence WCA=-WAB-WBC For case A, if both WAB, WBC>0, then WCA<0. Else its greater than zero. It is not possible for WCA=WBC because it will contradict the given statement. (Let WAB=WBC=x and other be equal to y. Then 2x=y and x=y which is not possible). Hence for A: q,s. Given answer: q,s Moving onto case C, again q is true. But r can't be true since they have opposite signs. s can also be true. Hence for C: q,s Given answer: q,r,s Are they considering only the magnitude?