Set 8: Central Ideas (Advanced)
Explanation
PASSAGE
The following text outlines the history of a technology. The Internet is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It began in the 1960s as a way for government researchers to share information. Computers in the '60s were large and immobile, and in order to make use of information stored in any one computer, one had to either travel to the site of the computer or have magnetic computer tapes sent through the conventional postal system. The Cold War spurred interest in a decentralized network that could survive attack, leading to ARPANET, the precursor to the modern Internet.
What primary problem did the early Internet aim to solve?
Detailed Explanation
This question asks you to identify the main point of the passage. Choice C is the best answer. The text explains that computers were 'large and immobile' and sharing info required travel or mailing tapes. The Internet began as a way 'to share information' without these physical constraints. This matches Choice C.
Choice B is incorrect because electricity costs are not mentioned.
Choice A is incorrect because entertainment is not mentioned.
Choice D is incorrect because replacing the postal system wasn't the primary goal, but rather a workaround for sending data tapes. Remember that supporting details help prove the central idea but are not the main point themselves. The author's central idea should be broad enough to encompass the entire passage while still being specific enough to be meaningful. Ask yourself what the author most wants you to understand.
Key Evidence:
• "share information"
• "Computers in the '60s were large and immobile"
Why others are wrong: B (Irrelevant - not mentioned), A (Irrelevant - not mentioned), D (Unsupported - text discusses data sharing).
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