A.I. Explanation:

Correct answer: practised

Explanation: The word 'practised' fits grammatically as it is the past participle form of the verb 'practice,' which is appropriate here to indicate actions performed by naturopaths, chiropractors, and acupuncturists. It aligns contextually with the sentence, as it describes the actions these professionals engage in regarding complementary therapies.

Meaning: 'Practised' means to have engaged in an activity or skill repeatedly to improve or maintain proficiency, in this case, referring to the therapies performed by health practitioners.

Wrong options:

• adjusted: 'Adjusted' implies making changes or modifications, which does not accurately describe the act of performing therapies.
• prompted: 'Prompted' suggests being encouraged to act, which does not fit the context of actively performing therapies.
• produced: 'Produced' indicates creating or manufacturing something, which is not applicable to the context of therapies being performed.

Correct answer: decades

Explanation: The word 'decades' is the plural form of 'decade,' which refers to a period of ten years. It fits grammatically and contextually, as the sentence discusses a time frame over which the popularity of complementary therapies has increased.

Meaning: 'Decades' means a period of ten years, indicating that the popularity of these therapies has grown over a significant length of time.

Wrong options:

• days: 'Days' refers to a much shorter time frame, which does not align with the context of increasing popularity over a longer period.
• times: 'Times' is too vague and does not specify a measurable period like 'decades' does.
• things: 'Things' is not a time measurement and does not fit the context of discussing a duration.

Correct answer: enthusiasm

Explanation: The word 'enthusiasm' fits well as it conveys a strong excitement or eagerness, which is contextually appropriate when discussing interest in alternative lifestyles. It also aligns grammatically as a noun that complements the sentence structure.

Meaning: 'Enthusiasm' means intense and eager enjoyment, interest, or approval, indicating a positive attitude towards alternative lifestyles.

Wrong options:

• happiness: 'Happiness' refers to a state of well-being or contentment, which does not directly relate to the interest in lifestyles.
• joy: 'Joy' is an emotion similar to happiness but does not convey the active interest implied in the context.
• fun: 'Fun' refers to enjoyment or amusement, which is not suitable for describing a serious interest in lifestyles.

Correct answer: influence

Explanation: The word 'influence' is appropriate as it indicates the capacity to have an effect on the character, development, or behavior of someone or something. It fits grammatically and contextually, as it describes the impact of immigration and trade with China on the status of complementary therapies.

Meaning: 'Influence' means the power to affect someone or something, indicating how external factors have shaped the popularity of these therapies.

Wrong options:

• interest: 'Interest' refers to a feeling of wanting to know or learn about something, which does not fit the context of having an effect.
• activity: 'Activity' refers to a state of being active or engaged, which does not convey the idea of impact or effect.
• accuracy: 'Accuracy' refers to correctness or precision, which is unrelated to the context of influence.

Correct answer: efficacy

Explanation: The word 'efficacy' fits grammatically as a noun that refers to the ability to produce a desired or intended result. It is contextually relevant as the sentence discusses scientific research into the effectiveness of complementary therapies.

Meaning: 'Efficacy' means the ability to produce a desired or intended result, particularly in the context of therapies being effective.

Wrong options:

• aspects: 'Aspects' refers to different parts or features, which does not specifically address the effectiveness of therapies.
• effects: 'Effects' refers to the results of an action, but does not convey the idea of effectiveness as directly as 'efficacy.'
• access: 'Access' refers to the means of approaching or entering a place, which is unrelated to the effectiveness of therapies.