To use one of the C++ built-in mathematical functions, you must include the _____ header file in your program A. calculation.h B. compute.h C. expression.h D. math.h E. mathematical.h

The correct answer is D. math.h

The math.h header file contains declarations for a number of mathematical functions, such as sin(), cos(), tan(), atan(), sqrt(), pow(), and log(). These functions can be used to perform basic mathematical operations on numbers.

The calculation.h, compute.h, and expression.h header files do not exist.