A Disadvantage of the North American Industry Classification System (NAICS)is

A disadvantage of the North American Industry Classification System (NAICS) is that:

A) it only lists the top ten firms in any particular industry.
B) it is too difficult and confusing to read.
C) it assigns one code to each organization based on its major economic activity, so large firms that engage in many different activities are given only one code.
D) it only covers organizations with sales in excess of (US) $1 million.