Explanation
In this vocabulary item, Burden is the closest synonym of Encumber, so option B is correct. The word Encumber and the word Burden share the same central sense in the context tested by the question, although usage, tone and grammatical form should still be checked before substituting one for the other. A synonym is not required to be identical in every possible sentence; it must preserve the intended meaning in the relevant context. Here, replacing Encumber with Burden keeps the core idea intact without reversing the tone or changing the action, quality or state expressed by the target word. The alternatives Horrify, Desire and Magnificent do not express the same central meaning as Encumber. This distinction matters because competitive examinations often place one accurate synonym beside three familiar but contextually unsuitable words. To verify Encumber independently, identify its part of speech, state a short definition, and place both Encumber and Burden in the same simple sentence. If the sentence retains its essential meaning and grammatical structure, the synonym relationship is supported. Learners should revise Encumber together with Burden, a brief usage cue and the contrasting distractors.