Write a C$++$ function that will work as a mark calculator.The program should have a function called MarkCalc$()$ which receives three parameters: the marks of $2$ courses $($double$)$ and an option $($int$)$ from the user. The function should work as follows, using an if$\_$else chain or switch: If option is $1$The function will return the maximum mark out of the $2$ passed marksIf option is $2$The function will return the average of the passed $2$ marksOtherwiseThe function will return $-999\mathrm{.}00$ At the beginning of the program, type your full name and your ID as a comment.In the main $()$ prompt the user to enter the $2$ marks and the option, then call the function MarkCalc$()$ properly. PS: The function should return a double value.In the main$()$ function, display the result of calling the function MarkCalc$().$Create a function prototype and function difinition for all functions.USE appropriate input$/$ output messages and correct data types.