Angular Deck#254/282PrevNextQuestion 254 of 282Hard#angular#dependency-injectionWhat are the types of injector hierarchies?by TimmoOct 7, 20260 viewsHelpful0SharePractice with AIShow Answer (Space)Self-rating (1 / 2):Needs ReviewMasteredMastered & NextPrevShowAIMasteredNextPrevious (#253/282)What is an optional dependency?Next Question (#255/282)What are reactive forms?Keyboard shortcuts: ← / → prev/next · Space toggle answer · 1 Mastered · 2 Needs Review.