Unrestricted submarine warfare is a type of naval warfare in which submarines sink vessels such as freighters and tankers without warning, as opposed to attacks per prize rules (also known as "cruiser rules").
A and B is out because these undoubtedly are unique Chinese achievements. So is D. The Chinese are infamous for these things. Other achievements include gunpowder, fireworks, ect.
C is basically the answer because the chinese aren't the only race or country to do so. Many people have done it in the past before them and present in the terms of civilization. It isn't simply uniquely or originally from them.
Answer:
C. the vulnerability to invaders from the north is the correct answer.
Explanation:
The initial sit-ins during the birmingham campaign of 1963 were recieved with low turnout because many people paid little attention to them.
<h3>The Birmingham campaign. </h3>
The Birmingham campaign were a series of civil protest aimed at stopping racial discrimination against African Americans in Birmingham, Alabama.
These civil disobedience involved a series of sit-ins carried out by blacks to protest the negative racial stratification which was evident at that time.
Initially, the sit-ins did not receive enough support because many people did not pay attention to them.
Learn more about the Birmingham campaign at brainly.com/question/16526142
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