Interrupt chaining

A$.$ allows CPU to defer processing of low$-$priority interrupts without masking all interrupts.

B$.$ splits interrupt management between first level and second level interrupt handlers.

C$.$ is used to handle interrupts but not exceptions.

D$.$ is a compromise between the overhead of a huge interrupt table and the inefficiency of dispatching to a

single interrupt handler.

In memory$-$mapped $\frac{1}{0}$

A$.$ main memory of the computing device is used for communicating with the $\frac{1}{O}$ devices using the

standard $\frac{1}{O}$ instructions.

B$.$ main memory of the computing device is used for communicating with the l$/$O devices using the speci

$1/$O instructions.

C$.$ address space of the computing device is used for communicating with the I$/$O devices using the

standard $\frac{1}{O}$ instructions.

D$.$ address space of the computing device is used for communicating with the I$/$O devices using the spec

$1/$O instructions.

A relative path name defines a path from

A$.$ the root directory

B$.$ the current directory

C$.$ from the UFD $($user file directory$)$

D$.$ from the MFD $($master file directory$)$

If a current directory is$/$home$/$user$/$ashok and then the proposed path to file$/$home$/$user$/$jill$/$hello$.$c

i$.$

A$../$jill$/$hello$.$c

B$.../../$jill$/$hello$.$c

C$.../$jill$/$hello$.$c

D$./$jill$/$hello$.$c

UNIX systems employ.

A$.$ two$-$level tree directory

B$.$ general graph directory

C$.$ single$-$level directory

D$.$ acyclic$-$graph directory