ANS:C - Vacuum pump

Among the options provided, the device that typically has the maximum compression ratio is the compressor.

Explanation:

1. Compression Ratio:
   • Compression ratio is defined as the ratio of the absolute discharge pressure to the absolute suction pressure in a compression process.
   • It indicates how much the compressor increases the pressure of the fluid (gas or air) passing through it.
2. Devices Listed:
   • Blower: Blowers are used to move air or gas with a moderate increase in pressure. They generally have lower compression ratios compared to compressors.
   • Compressor: Compressors are designed specifically to increase the pressure of gases or air to higher levels. They can achieve high compression ratios, especially in applications such as gas turbines, refrigeration systems, and industrial processes.
   • Vacuum Pump: Vacuum pumps are designed to evacuate or reduce the pressure below atmospheric pressure. They do not typically operate with compression ratios in the same sense as compressors.
   • Fan: Fans are used to move air or gases with relatively low pressure increases. They generally have the lowest compression ratios among the devices listed.
3. Maximum Compression Ratio:
   • Compressors, especially those used in high-pressure applications like gas compression in industrial processes or refrigeration systems, are designed to achieve significantly higher compression ratios compared to blowers, vacuum pumps, or fans.
   • The actual compression ratio can vary depending on the specific type and design of the compressor, but compressors are generally engineered to handle much higher pressure differentials than other devices listed.

Conclusion: