Here, your expression is: 20x^6y+40x^4y^2−10x^5y^5
Now, your coefficients are: 20, 40, 10
So, GCF of 20, 40 & 10 is 10
& Greatest common variable of x^6y, x^4y & x^5y^5 is x^4y
So, Your GCF for whole expression is 10x^4y
In short, Your Answer would be Option B
Hope this helps!
