Right choice is (a) 10x+2
Explanation: We know that,
f(x)=q(x)×g(x)+r(x)
Where, f(x) is the dividend, q(x) is the quotient, g(x) is the divisor and r(x) is the remainder.
∴ 50x^2-90x-25=q(x)×5x-10-5
50x^2-90x-25+5=q(x)×5x-10
\(\frac {50x^2-90x-20}{5x-10}\)=q(x)
We get, q(x)=10x+2