A.

\(-\frac{896x^6}{9}\)

B.

\(-\frac{896x^5}{9}\)

C.

\(-\frac{896x^5}{27}\)

D.

\(-\frac{896x^6}{27}\)

Correct answer is **C**

rth term of a binomial expansion =\(^nC_r-1 a^{n-(r-1)}b^{r-1}\)

\(n = 10,r = 6 \therefore r-1=5\)

6th term =\(^{10}C_5 1^{10} - 5 (-\frac{2}{3}x)^5\)

\(=252*1*-\frac{32x^5}{243}=-\frac{896x^5}{27}\)