Oligopoly is a state of limited competition, in which a market is shared with a small number of producers or sellers. The most clear example of this is the second option.
In the smarphone business, the operating system market is dominated by IOS and Android and it's almost impossible for a new software provider to enter the marker and be successful at it.
Hope this helps!
ANSWER : Risk control develops safeguards that reduce risks and their impact
Items were rationed and very sparse such as butter, sugar, and gas so they had to endure a shortage of many items.
