Correct Answer: B

Rationale: The word 'riddled' in this context means filled with or affected by (something undesirable) to a great degree, which aligns with the definition of 'overrun.' In this sentence, the cavity is described as being full of infection, indicating that the infection has spread extensively throughout. 'Challenged' (choice A) implies being tested or provoked, which is not the meaning conveyed by 'riddled.' 'Separated' (choice C) means divided or isolated, which does not fit the context of the sentence. 'Complete' (choice D) means finished or whole, which is the opposite of what is described in the sentence where the cavity is full of infection.

Correct Answer: A

Rationale: The correct answer is A: "convulsion." A paroxysm is defined as a sudden spasm or convulsion. The word "convulsion" specifically refers to a violent and involuntary contraction or spasm of muscles, which aligns perfectly with the description of a paroxysm. On the other hand, choices B, C, and D are incorrect. "Symptom" (B) refers to a manifestation of a condition rather than a physical spasm. "Efficacy" (C) relates to effectiveness or success, not a sudden spasm. "Embolism" (D) refers to the obstruction of a blood vessel, which is unrelated to the concept of a sudden spasm. Therefore, convulsion is the most suitable synonym for a paroxysm in this context.

Correct Answer: C

Rationale: In this context, 'projected' is used to indicate an estimation or prediction of the duration of the treatment. Therefore, it aligns closest in meaning to 'estimated.' Choice A, 'Protruded,' means to extend beyond or above a surface, which does not fit the context of the sentence. Choice B, 'Guaranteed,' means to provide assurance, which is not the intended meaning in the sentence. Choice D, 'Alleged,' means to claim without proof, which is not the correct interpretation in this context.

Correct Answer: D

Rationale: A restricted diet is limited in some way, such as reducing the intake of certain foods, food groups, or nutrients. It may involve limitations on quantity, frequency, or types of foods consumed. This restriction could be related to health factors, allergies, sensitivities, ethical reasons, or personal preferences. Choice A, 'low in fat,' is too specific and does not encompass the broad concept of restriction in a diet. Choice B, 'vegetarian,' refers to a specific dietary pattern but does not necessarily indicate restriction. Choice C, 'banned,' is incorrect as it implies a complete prohibition rather than limitation, which is characteristic of a restricted diet.

Correct Answer: B

Rationale: The word 'riddled' in this context means filled with or affected by (something undesirable) to a great degree, which aligns with the definition of 'overrun.' In this sentence, the cavity is described as being full of infection, indicating that the infection has spread extensively throughout. 'Challenged' (choice A) implies being tested or provoked, which is not the meaning conveyed by 'riddled.' 'Separated' (choice C) means divided or isolated, which does not fit the context of the sentence. 'Complete' (choice D) means finished or whole, which is the opposite of what is described in the sentence where the cavity is full of infection.