Pipe Question Explained
This worked Linux Command Line practice question tests Shell Basics. Try the answer first, then review why B is the best choice.
Short answer
The correct answer is B. Sends one command output into another command input.
A pipe connects stdout from the command on the left to stdin of the command on the right. For example, ps aux | grep nginx. The key is to match the exact action in the prompt to the tool, command, or concept that performs that action directly. Here, B. Sends one command output into another command input is the only option that satisfies the scenario without adding unrelated behavior.
The Question
What does the pipe operator | do?
Why B is correct
A pipe connects stdout from the command on the left to stdin of the command on the right. For example, ps aux | grep nginx. The key is to match the exact action in the prompt to the tool, command, or concept that performs that action directly. Here, B. Sends one command output into another command input is the only option that satisfies the scenario without adding unrelated behavior.
Why the other options are wrong
Option A does not match the requirement in the prompt. The correct answer is B because A pipe connects stdout from the command on the left to stdin of the command on the right. For example, ps aux | grep nginx.
Option C does not match the requirement in the prompt. The correct answer is B because A pipe connects stdout from the command on the left to stdin of the command on the right. For example, ps aux | grep nginx.
Option D does not match the requirement in the prompt. The correct answer is B because A pipe connects stdout from the command on the left to stdin of the command on the right. For example, ps aux | grep nginx.
Key idea: Shell Basics
Shell Basics questions test whether you can connect a common workflow problem to the right practical command, service, or concept. Instead of memorizing isolated definitions, look for the job being done in the prompt: staging a file, querying rows, running code, persisting container data, checking a service, or choosing the right cloud building block. The best answer usually names the simplest tool that performs that job directly. For Linux Command Line, the safest study pattern is to read the scenario, underline the action verb, and eliminate answers that solve a different problem. If an option sounds related but changes the scope, adds risk, or describes a different layer of the stack, it is probably a distractor. After choosing an answer, explain why the other three fail; that habit builds the practical judgment these quizzes are meant to measure.
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