FUNDAMENTALS OF COMPUTER

Detailed explanation-1: -Rules for naming variables: underscore( ). For beginning programmers, it may be easier to begin all variable names with a letter of the alphabet. After the first initial letter, variable names can also contain letters and numbers. No spaces or special characters, however, are allowed.

Detailed explanation-2: -Variable names can never contain spaces. The underscore character ( ) can also appear in a name. It is often used in names with multiple words, such as my name or price of tea in china .

Detailed explanation-3: -True, In C#, a variable name can start with the alphabet and underscore only. False, In C#, a variable name can start with an underscore but not start with a digit. Hence the correct answer is alphabet; underscore.

Detailed explanation-4: -Specifically, spaces are not permitted in the variable names, as variable name must be a single word.