The correct option is C 315×210
y=x4e2xu=e2xandv=x4y10=u10v+10C1u9v1+10C2u8v2+........+10C9uv9+10C10uv10
except v4=4!=24 all other derivatives of v are zero at x = 0 i.e
v(0)=v1(0)=.......vn(0)=0⇒y10=10C4u6v4un=2ne2xu6=26e2xu6(0)=26y10(0)=10C4×24×26
y10(0)=10×9×8×72×3×4×24×26=315×210