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Solution

Raster scan display forms an image using many small dots called pixels.

These pixels are scanned line by line from left to right and top to bottom.

Television display also works in a similar raster scanning manner.

So, Assertion A is true.

Reason R correctly explains why raster scan devices can use television monitors.

So, Reason R is also true and it is the correct explanation of Assertion A.

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Solution

Handshaking requires two control signals working in opposite directions.

So, (A) matches with II.

Programmed I/O requires the CPU to continuously check the I/O flag and perform the transfer.

So, (B) matches with IV.

In interrupt-initiated I/O, the I/O interface informs the CPU that the device is ready for transfer.

So, (C) matches with I.

An I/O processor has local memory and controls a large set of I/O devices.

So, (D) matches with III.

Final matching is:

A-II, B-IV, C-I, D-III

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Solution

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Solution

Isolated I/O uses separate instructions for I/O and memory communication.

So, (a) $\rightarrow$ (ii)

Memory mapped I/O uses same set of control signals for I/O and memory communication.

So, (b) $\rightarrow$ (i)

I/O interface resolves the difference between central computer and peripherals.

So, (c) $\rightarrow$ (iv)

Asynchronous data transfer requires control signals to be transmitted between communicating units.

So, (d) $\rightarrow$ (iii)

Hence, correct matching is:

$(a)-(ii),\ (b)-(i),\ (c)-(iv),\ (d)-(iii)$

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Solution

I/O Module is the basic level of I/O handling.

DMA is more advanced because it transfers data directly between memory and I/O device.

I/O Channel is more complex than DMA because it can control I/O operations more independently.

I/O Processor is the most complex because it is a specialized processor for I/O operations.

Increasing order:
$A,\ D,\ C,\ B$