The correct answer is: E. No Error
The sentence is grammatically correct. The word “that” is used to introduce a subordinate clause, which is a clause that cannot stand on its own as a complete sentence. In this case, the subordinate clause is “that patient should not have wasted time before coming for help.” The word “should” is used to express a recommendation or a suggestion. In this case, the doctor is recommending that the patient should not have waited so long to come for help. The word “not” is a negative adverb. In this case, it is used to negate the verb “wasted.” The word “time” is a noun that refers to a period of indefinite duration. In this case, it refers to the time that the patient waited before coming for help. The word “before” is a preposition that indicates a time that precedes another time. In this case, it indicates the time that the patient waited before coming for help. The word “coming” is a verb that means to move towards a place. In this case, it refers to the patient’s movement towards the doctor’s office. The word “for” is a preposition that indicates the purpose of an action. In this case, it indicates the purpose of the patient’s movement towards the doctor’s office, which was to get help.
The other options are incorrect because they either change the meaning of the sentence or make it grammatically incorrect.