A security alarm requires a four-digit code. The code can use the digits 0–9 and the digits cannot be repeated. Which expression can be used to determine the probability of the alarm code beginning with a number greater than 7? StartFraction (2 P 1) (9 P 3) Over 10 P 4 EndFraction StartFraction (2 C 1) (9 C 3) Over 10 C 4 EndFraction StartFraction (10 P 1) (9 P 3) Over 10 P 4 EndFraction StartFraction (10 C 1) (9 C 3) Over 10 C 4 EndFraction