$6.$ If the absolute pressure at a depth $\backslash ($ d $\backslash )$ in a lake is $\backslash ($ P $\backslash ),$ the absolute pressure at a depth $\backslash (2$ d $\backslash )$ will be

A$.\backslash (2$ P $\backslash ).$

B$.\backslash ($ P $\backslash ).$

C$.$ greater than $\backslash (2$ P $\backslash ).$

D$.$ less than $\backslash (2$ P $\backslash ).$