The number of double crosses will be equal to
A. $$\frac{{{\text{n}}\left( {{\text{n}} - 1} \right)}}{2}$$
B. $$\frac{{{\text{n}}\left( {{\text{n}} - 1} \right)\left( {{\text{n}} - 2} \right)\left( {{\text{n}} - 3} \right)}}{8}$$
C. $$\frac{{{\text{n}}\left( {{\text{n}} - 1} \right)\left( {{\text{n}} - 2} \right)}}{4}$$
D. $$\frac{{{\text{n}}\left( {{\text{n}} + 1} \right)\left( {{\text{n}} - 2} \right)}}{6}$$
Answer: Option B

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