ITPEC FE Morning April 2021 Question 48

Which of the following is the weakest module coupling?

a)To implement as many functions as possible with a single moduleb)To pass arguments that control another module’s logic when the module is calledc)To pass only required data items as arguments between two (2) modulesd)To use a global area to share data items with other modules

Explanation

Passing only the required data items as arguments — this is data coupling, the weakest kind of coupling between modules.

Coupling measures how much modules depend on each other. From weakest (best) to strongest:

•Data coupling: only the needed data items are passed as arguments
•Stamp coupling: a whole data structure is passed although only part of it is used
•Control coupling: a flag is passed that decides the called module's logic
•External coupling: modules share an externally defined data item or format
•Common coupling: modules share data in a global area
•Content coupling: one module refers directly to the inside of another

Answer (c)

Why not others:

•(a) — cramming many functions into one module is not a kind of coupling at all; it lowers cohesion and makes the module hard to maintain and reuse
•(b) — passing arguments that control the other module's logic is control coupling: the caller must know how the callee works inside
•(d) — sharing data through a global area is common coupling: any module can change the data, so a change affects every module that uses it

Key rule: Aim for low coupling and high cohesion: pass modules only what they need, and keep each module to one well-defined function.

System Development Technology · AI-written, may contain errors

Previous Next

Practice this exam

This question comes from an official ITPEC past paper. ITPEC Practice is an independent study tool and is not affiliated with ITPEC. See the official FE past-paper collection or Report an issue.