You want to maintain a single instance of a service shared across multiple lazy-loaded Angular modules. Which method ensures this singleton behavior?

hard📝 component behavior Q8 of 15

Angular - Services and Dependency Injection

AAdd the service to the <code>providers</code> array of each lazy-loaded module

BProvide the service only in the root injector using <code>@Injectable({ providedIn: 'root' })</code>

CDeclare the service in each lazy-loaded module's component providers

DCreate a new instance manually in each lazy-loaded module

Step-by-Step Solution

Solution:

Step 1: Understand lazy-loaded modules and injectors
Lazy-loaded modules have their own injectors, so providing a service in them creates separate instances.
Step 2: Use root injector for singleton
Providing the service in the root injector ensures one instance shared across all modules, including lazy-loaded ones.
Final Answer:
Provide the service only in the root injector using @Injectable({ providedIn: 'root' }) -> Option B
Quick Check:
Root injector shares singleton across lazy modules [OK]

Quick Trick: Use providedIn root to share singleton in lazy modules [OK]

Common Mistakes:

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