Computer & Information Technology

385

Q280. A memory organised as 4K locations of 8 bits each requires how many distinct address lines?

[SSC CGL Tier-II 2025 cycle (held 19 January 2026)]

1. 12
2. 8
3. 10
4. 16

Answer: A. 12

Explanation: Four kilobytes organised into 4096 individually addressable bytes require 4096 unique addresses. Since 4096 equals 2 raised to the twelfth power, twelve binary address lines select each location. The eight-bit word width determines data-bus width instead.

Q279. How is a copy-on-write snapshot unlike a full traditional backup at the instant it is taken?

[SSC CGL Tier-II 2025 cycle (held 19 January 2026)]

1. It initially references existing blocks and preserves blocks when changed
2. It must reside on another physical disk
3. It always requires the computer to shut down
4. It immediately duplicates every bit to a new drive

Answer: A. It initially references existing blocks and preserves blocks when changed

Explanation: Copy-on-write snapshots typically record references to existing data and retain original blocks as writes modify them. The initial snapshot can therefore be created rapidly without duplicating the full dataset. It is not necessarily an independent, off-device disaster-recovery backup.

Q278. What software architecture supports OLE object linking through the server’s persistent class identifier?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. BLOB indexing
2. AWT
3. SMTP
4. Component Object Model

Answer: D. Component Object Model

Explanation: Microsoft’s Component Object Model supplies object interfaces and identifiers used by Object Linking and Embedding. BLOB storage, Java’s AWT and the SMTP email protocol do not provide the required Windows object architecture.

Q277. Which Windows shortcut moves keyboard focus through programs pinned on the taskbar?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. Windows+T
2. Alt+Tab
3. Windows+Tab
4. Ctrl+Alt+Tab

Answer: A. Windows+T

Explanation: Windows+T moves selection among taskbar apps and can be used with other keys to act on the highlighted item. Alt+Tab changes application focus through a different interface.

Q276. Which OSI layer handles routing with logical network addresses?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. Physical
2. Data Link
3. Network
4. Presentation

Answer: C. Network

Explanation: The OSI network layer handles logical addressing and packet routing between networks. The data-link layer primarily serves local framing, and the physical layer transmits raw signals, not inter-network routes.

Q275. Which standard can encrypt the content of email messages end-to-end?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. S/MIME
2. IMAP
3. SSL alone
4. SMTP

Answer: A. S/MIME

Explanation: S/MIME is a standard for cryptographic protection of MIME email messages, including encryption and digital signatures. IMAP accesses messages, SMTP transports them, and TLS normally protects a communication link rather than the stored message itself.

Q274. Which behaviour is characteristic of a malicious Trojan horse?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. Stealing files or installing a backdoor
2. Flooding links to cause congestion
3. Overwhelming servers with traffic
4. Self-copying automatically like a worm

Answer: A. Stealing files or installing a backdoor

Explanation: A Trojan masquerades as trusted software and may steal information, delete content or open backdoors. It does not inherently propagate by copying itself, unlike a worm, or necessarily act as a traffic-flooding tool.

Q273. What is the principal security benefit of encrypting network data while it is transmitted?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. Making intercepted content unintelligible
2. Preventing physical theft
3. Increasing transfer speed
4. Blocking every unauthorised login

Answer: A. Making intercepted content unintelligible

Explanation: Encryption in transit prevents an eavesdropper from easily reading captured packets without the necessary cryptographic keys. It is not a replacement for access control, endpoint security, or physical protection of hardware.

Q272. What difficulty commonly arises with shared-key cryptographic communication?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. Always slower than public-key cryptography
2. Cannot protect files at rest
3. Securely distributing and managing shared keys
4. Requires no computing resources

Answer: C. Securely distributing and managing shared keys

Explanation: Symmetric encryption requires communicating parties to possess the same secret key. Delivering, rotating and protecting that key securely becomes increasingly demanding as the number of communicating parties grows.

Q271. Why compress a file before uploading it to cloud storage?

[SSC CGL Tier-II 2025 cycle, held 19 January 2026]

1. Convert it to an authenticated format
2. Reduce upload size and storage requirements
3. Guarantee encryption
4. Make it universally executable

Answer: B. Reduce upload size and storage requirements

Explanation: Compression reduces redundant information so the file can occupy fewer bytes, potentially cutting upload time and cloud storage use. Compression by itself does not authenticate, encrypt or make arbitrary files executable.