Answer: (iv) All of the Above

Explanation

A lexeme is the actual sequence of characters in the source program that matches the pattern of a token. The scanner groups the characters of int total = 25; into these lexemes:

Lexeme	Token class
int	keyword
total	identifier
=	assignment operator
25	integer constant
;	separator

So int, total and 25 are all lexemes.

$$\boxed{\text{(iv) All of the Above}}$$