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Frontend Performance Quiz Practice
Active Recall Drill Session
← Exit Session
Question 1 of 1
hard
Frontend Performance
In the Try It scenario, what could cause formatCurrency and debounce to remain in the final bundle even though only formatDate is imported?
A
This is impossible — unused exports are always removed
B
A top-level side effect in utils.js that makes the bundler conservatively keep the whole module, or using CommonJS require() instead of ESM import, both of which can defeat tree-shaking
C
Tree-shaking only works for CSS, never JavaScript
D
The file extension being .js instead of .mjs always prevents tree-shaking
Check Answer