$\begin{array}{1 1}(A)\;\text{5000 ways}\\(B)\;\text{5040 ways}\\(C)\;\text{5060 ways}\\(D)\;\text{5080 ways}\end{array} $

First letter of the code word can be selected in 10 ways.After the selection of first letter,we have 9 letters.Hence the second letter can be selected in 9 ways.According to FPC,first two letters can be selected in $10\times 9$ ways

Similarly third letter can be selected in 8 ways,under the fourth letter can be selected in 7 ways.According FPC,number of ways of selecting four letters out of 10 letters of english alphabet.

$\Rightarrow 10\times 9\times 8\times 7$ways

$\Rightarrow 5040$ways

Hence (B) is the correct answer.

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