In global competition

A each competitor typically charges a single price for its product$/$service worldwide.

$($B$)$ a company's overall global market share is the sum of its market shares in each country market where its product$/$service is sold.

$($C$)$ a firm's overall global competitive advantage is determined by the sum of the sizes of the competitive advantages it has in each of its profit sanctuaries.

$($D$)$ competitive conditions across national markets are linked strongly enough to form a true global or world market, and leading competitors compete head$-$to$-$head in many different countries.

the leading companies compete for having the biggest share of the world market, but only occasionally compete head$-$tohead in different countries.