What is the correct way to declare an integer variable named "number" in C++?

The declaration of an integer variable in C++ follows a specific syntax that adheres to the rules of the language. The correct way to declare an integer variable named "number" is to use the keyword that denotes the data type followed by the variable name. In this case, "int" is the keyword that represents the integer data type in C++. Thus, writing "int number;" successfully declares the variable "number" as an integer.

This approach clearly indicates to the compiler that the variable should hold integer values, enabling proper memory allocation and type checking. The other choices do not conform to the C++ variable declaration syntax. For example, "number int" places the variable name before the data type, which is not valid. "integer number" uses a data type that does not exist in C++; the correct keyword is "int." Lastly, "var number int" introduces an unnecessary keyword, "var," which is not used in C++ for declaring variables. Therefore, the syntax "int number;" is the correct and standard way to declare an integer variable in C++.