In each sentence, a part is given in bold, which may or may not be grammatically correct. If incorrect, replace it with the best alternative among the given options. If correct, choose “No correction required” as your answer choice.

Matters will remain disorient until the king acts decisively, according to the power vested in him.

Correct option is D

The correct answer is: “ will remain disoriented unless”.
This option is the correct answer. "Will remain disoriented unless" indicates a future condition where matters will continue to be disoriented unless the king acts decisively. This option correctly uses the future tense to convey the intended meaning.
Incorrect options:
(a) will remained disoriented unless
This option is grammatically incorrect because it uses the past tense form "remained" with the future tense "will." The correct form should be "will remain disoriented unless," which indicates a future possibility if certain conditions are not met.
(b) would remained disorient until
This option is also grammatically incorrect because it uses the past tense form "would remained" with the conjunction "until." Additionally, ‘would’ always followed by base (remain) form of the verb. We need the adjective form of ‘disorient’, thus the correct form should be ‘disoriented’. The correct form should be "will remain disoriented unless," which indicates the continuation of the state of disorientation until a specific time or action.
(c) has remain disoriented unless
This option is grammatically incorrect because it uses the present perfect tense "has remain," which is not suitable in this context. The correct form should be "will remain disoriented unless," as it refers to a future possibility.
In conclusion, option " will remain disoriented unless" is the best alternative that fits both grammatically and contextually with the sentence. It conveys the idea that matters will continue to be disoriented unless the king acts decisively, as per the power vested in him.