4. (4)5 =
a. 12
b. 13
c. 14
d. 15
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[tex]▪▪▪▪▪▪▪▪▪▪▪▪▪ {\huge\mathfrak{Answer}}▪▪▪▪▪▪▪▪▪▪▪▪▪▪[/tex]
therefore, the Correct choice is d) 15