Which of the following statements about named constants is/are true?

A named constant must be initialized with a value at the time it is declared.

The identifier name of a named constant can only contain capital letters and underscores.

The initial value of a named constant, cannot be changed during the program execution.

All 3 of these statements are true.

Statements A named constant must be initialized with a value at the time it is declared and The initial value of a named constant, cannot be changed during the program execution are true, but The identifier name of a named constant can only contain capital letters and underscores is not.