Answer:
D
Step-by-step explanation:
The diagram shows Pascal's triangle. Pascal's triangle is a triangular array of the binomial coefficients.
The entry in the [tex]n^{th}[/tex] row (start counting rows from 0) and [tex]k^{th}[/tex] column (start counting columns from 0) of Pascal's triangle is denoted by
[tex]C^n_k=\left(\begin{array}{c}n\\ k\end{array}\right)[/tex]
Coefficient 20 stands in 6th row, then n = 6 and in 3rd column, so k = 3.
Hence,
[tex]20=C^6_3=\left(\begin{array}{c}6\\ 3\end{array}\right)=\dfrac{6!}{3!(6-3)!}[/tex]
