The question is from the OG book practice exam
Eqn of line : y = mx+b
let y intercept be (0,b)
then x intercept (y= 0)
0 = mx+b
\frac{-b}{m}=x -->Eqn1
x intercept = 2 (y) intercept (A)
\frac{-b}{m} = 2b
\frac{-1}{2}=m, where m is the slope
I guess all of them are individually sufficient to find the slope as negative first condition was explained by @HoldMyBeer
B) x intercept= -b/m and y intercept is b so product is
-b^2/m for this quantity to be positive u need m to be negative
C) slope is (b-s)/(a-r) as we know from the given condition in option either one has to be negative hence slope is negative in this case aswell