Concept:When two fractions are equal, cross-multiply to eliminate the denominators and form a linear equation.Explanation:Start with the given proportion: 19−3y1−9y=85.Cross-multiply: 8×(1−9y)=5×(19−3y).Expand both sides: 8−72y=95−15y.Bring all y terms to one side and constants to the other: −72y+15y=95−8.Simplify: −57y=87.Divide both sides by −57: y=−5787.Reduce the fraction by dividing numerator and denominator by 3: y=−1929.Answer:The value of y is −1929, which matches option C.