Bank PO / Clerk / RBI - MCQ Practice Questions

Understanding:

We need to identify the primary function of cache memory in a computer system.

Step 1: Define Cache Memory

Cache memory is a small, extremely fast memory unit located either on the CPU chip itself or very close to it. It acts as a buffer between the CPU and the main memory (RAM).

Step 2: Understand its purpose

The CPU can access cache memory significantly faster than it can access RAM. When the CPU needs data, it first checks the cache. If the data is found (cache hit), it is retrieved almost instantly. If not (cache miss), the CPU fetches it from RAM and stores a copy in cache for future use. This dramatically reduces average memory access time.

Step 3: Rule out other options

Permanent OS storage is the role of ROM/hard drive. Large file storage is handled by secondary storage (HDD/SSD). I/O management is the role of device controllers and the OS kernel.

Answer:

Cache memory primarily stores frequently accessed data and instructions so the CPU can retrieve them faster than from RAM.

Quick Tip:

Cache is organised in levels: L1 (smallest, fastest, on-chip), L2, and L3 (larger, slightly slower). The closer the cache is to the CPU core, the faster but smaller it is.

Understanding:

We need to identify the correct description of a compiler in the context of computer programming.

Step 1: Define Compiler

A compiler is a special program (system software) that reads the entire source code written in a high-level language (such as C, C++, or Java) and translates it completely into machine code (binary) or an intermediate code before the program is executed.

Step 2: Distinguish from an Interpreter

An interpreter translates and executes the source code line-by-line at runtime — this matches option A, which describes an interpreter, not a compiler. Compiled programs generally run faster because translation is done beforehand.

Step 3: Rule out other options

A hardware unit for floating-point arithmetic is called an FPU (Floating Point Unit). Memory allocation management is handled by the OS memory manager or garbage collectors, not a compiler.

Answer:

A compiler translates the entire high-level source code into machine code before the program is executed.

Quick Tip:

Examples of compiled languages: C, C++, Fortran. Examples of interpreted languages: Python, JavaScript (traditionally). Java uses both — compiled to bytecode, then interpreted/JIT-compiled by the JVM.

Understanding:

We need to identify the Windows keyboard shortcut that deletes a file permanently without sending it to the Recycle Bin.

Step 1: Standard delete behaviour

When a user presses the Delete key alone, the selected file is moved to the Recycle Bin, from where it can be restored. This is a soft delete.

Step 2: Permanent delete shortcut

Pressing Shift + Delete bypasses the Recycle Bin entirely and permanently removes the file from the file system. Windows displays a confirmation prompt warning the user that the file cannot be recovered from the Recycle Bin.

Step 3: Rule out other options

Ctrl + D in many applications moves items to the Recycle Bin (similar to plain Delete) or bookmarks a page in browsers. Alt + Delete and Ctrl + Shift + D are not standard Windows file deletion shortcuts.

Answer:

The keyboard shortcut Shift + Delete permanently deletes a file in Windows, bypassing the Recycle Bin.

Quick Tip:

Files deleted with Shift + Delete may still be recoverable using data recovery software if the disk sectors have not been overwritten. True permanent deletion requires dedicated disk-wiping tools.

Understanding:

We need to identify the SQL command that removes an entire table (its structure and all its data) permanently from the database.

Step 1: Differentiate the SQL commands

DELETE: a DML (Data Manipulation Language) command that removes specific rows from a table based on a WHERE clause. The table structure remains intact and the operation can be rolled back. TRUNCATE: a DDL command that removes all rows from a table instantly but keeps the table structure. It cannot be rolled back in most databases. DROP: a DDL (Data Definition Language) command that permanently removes the entire table — both its structure (schema) and all its data — from the database. It cannot be rolled back. REMOVE: not a valid standard SQL command.

Step 2: Match to the requirement

The question asks for removal of the table itself (not just its rows), so the correct command is DROP.

Answer:

The SQL command DROP is used to permanently remove an existing table along with all its data and structure from a database.

Quick Tip:

Remember the hierarchy: DELETE removes rows (can use WHERE), TRUNCATE removes all rows (keeps structure), DROP removes the entire table. DELETE is DML; TRUNCATE and DROP are DDL commands.