Which of the following, if any, are valid names for variables?

class
friend
#OnHand
void E. None of the above are valid names for variables

The correct answer is: E. None of the above are valid names for variables.

A variable name must start with a letter, underscore (_), or dollar sign ($). It can also contain digits (0-9) and underscores. The first character cannot be a digit.

The following are not valid variable names:

  • class: This is a reserved word in Java. Reserved words are used by the Java language and cannot be used as variable names.
  • friend: This is also a reserved word in Java.
  • OnHand: This name contains a pound sign (#), which is not allowed in Java variable names.

  • void: This is a keyword in Java, which is used to declare a method that returns nothing. Keywords cannot be used as variable names.

Therefore, none of the above options are valid names for variables.