Explanation: The computer boots from the device with the highest priority. Setting the SSD as the first boot device allows the installed OS to load instead of booting from the network.

Two-Factor Authentication (2FA):

2FA is a security method that requires two different authentication factors to verify a user's identity before granting access.

Types of Authentication Factors:
1. Something You Know: Password or PIN.
2. Something You Have: Smartphone OTP or security token.
3. Something You Are: Fingerprint or facial recognition.

CIA Triad:

The CIA Triad is a basic information security model consisting of three principles:

1. Confidentiality: Ensures that data is accessible only to authorized users.

2. Integrity: Ensures that data remains accurate, complete, and unaltered.

3. Availability: Ensures that systems and data are accessible to authorized users whenever needed.

Three Main Components of a URL

Given URL: https://www.bb.org.bd/index.php

1. Protocol (Scheme): https://
It defines the communication protocol used to transfer data securely between the browser and the web server.

2. Domain Name (Host): www.bb.org.bd
It is the human-readable address of the web server. Here, it refers to the Bangladesh Bank website.

3. File Path (Resource): /index.php
It identifies the requested resource on the server, such as the PHP script used to generate a webpage.

1. More Simultaneous Applications: RAM Upgrade (8 GB to 16 GB)
RAM stores the data and instructions of running applications. Increasing RAM allows more applications to run simultaneously and smoothly.

2. More Data Storage: SSD Upgrade (256 GB to 512 GB)
SSD provides permanent storage for the Operating System, software, documents, and other files. Increasing SSD capacity allows more data to be stored.

(a) Remaining Mailbox Storage:

Total Quota = 2 GB = 2,000 MB

Total Used = 350 + 1,250 + 0.9 + 120 = 1,720.9 MB

Remaining Storage = 2,000 − 1,720.9 = 279.1 MB

(b) To Receive a 300 MB File:

Required Space = 300 − 279.1 = 20.9 MB

The recipient should free up at least 20.9 MB of mailbox storage, preferably 21 MB, by deleting unnecessary emails and emptying Trash. Alternatively, the sender can share the file through Google Drive or OneDrive.

Advantages of Mobile Banking:

1. 24/7 Accessibility: Allows transactions anytime and anywhere without visiting a bank.

2. Financial Inclusion: Provides banking services to rural and unbanked people.

3. Time and Cost Efficiency: Saves time, travel costs, and transaction expenses.

4. Instant Transactions: Enables quick fund transfers and bill payments.

5. Automated Tracking: SMS alerts and digital statements help monitor transactions and expenses.

Challenges of Mobile Banking:

1. Security and Fraud Risks: Users may face phishing, SIM swapping, malware, and credential theft.

2. Network Infrastructure: Poor internet or mobile network coverage can interrupt services.

3. Digital Illiteracy: Some users struggle to operate mobile banking applications safely.

4. Device Dependency: Services depend on a functioning mobile device and sufficient battery power.

5. System Downtime and Limits: Server outages and transaction limits may delay payments or transfers.

Three Fundamental Principles of Information Security:

1. Principle of Least Privilege (PoLP): Users and applications should receive only the minimum access permissions necessary to perform their tasks. This reduces the risk of unauthorized access and damage.

2. Defense in Depth: Multiple layers of security, such as firewalls, MFA, antivirus, and encryption, are used to protect systems. If one layer fails, other layers provide additional protection.

3. Non-Repudiation: Ensures that a person cannot deny an action or message they have performed or sent. Digital signatures and audit logs help establish proof.