There are two self-defense techniques used by the monsters on Monster Island: spitting fire balls and blowing freezing wind. Every monster on Monster Island can spit fire balls or can blow freezing wind or can do both. There are 26 monsters on Monster Island. Of the monsters who can spit fire balls, 8 also blow freezing wind. How many of the monsters on Monster Island can use only one of the two self-defense techniques?

GMAT QUANT Problem Solving Level 500, Overlapping Sets

There are two self-defense techniques used by the monsters on Monster Island: spitting fire balls and blowing freezing wind. Every monster on Monster Island can spit fire balls or can blow freezing wind or can do both. There are 26 monsters on Monster Island. Of the monsters who can spit fire balls, 8 also blow freezing wind. How many of the monsters on Monster Island can use only one of the two self-defense techniques?

A. 4
B. 8
C. 10
D. 18
E. 26