Q. What is the use of NUL in MS-DOS? (A) It’s a directory (B) It’s a black hole device (C) It’s a file manager (D) It’s a keyboard driver 👁️ Show Answer 💬 Discuss 🔗 Share ⚡Menu ✅ Correct Answer: (B) It’s a black hole device Explanation: NUL is a special device file that discards all data written to it.