Meaning: 'Triggered' means to cause something to happen or to initiate an event.

Wrong options:

• started: 'Started' is a simple past verb that could fit, but it lacks the specific connotation of causing an event to occur, which 'triggered' conveys more effectively.
• poor: 'Poor' is an adjective that describes a lack of quality or resources, which does not fit the context of causing an event.
• expensive: 'Expensive' is an adjective that refers to high cost, which is irrelevant to the action of causing the mud volcano.
• exploratory: 'Exploratory' is an adjective that describes something intended for investigation, which does not relate to the action of causing the mud volcano.
• render: 'Render' is a verb that means to make or cause to become, but it does not fit as a cause for the mud volcano.
• escape: 'Escape' is a verb that refers to getting away from a situation, which does not fit the context of causing the mud volcano.

Correct answer: render

Explanation: The verb 'render' fits grammatically as it indicates the action of making something into a certain state. In this context, it suggests that the countryside will be made uninhabitable due to the mud volcano.

Meaning: 'Render' means to cause to be or to make something into a particular state.

Wrong options:

• triggered: 'Triggered' is a past participle that indicates the action of causing something to happen, but it does not fit the context of making something uninhabitable.
• started: 'Started' is a simple past verb that indicates the beginning of an action, which does not convey the sense of making something uninhabitable.
• poor: 'Poor' is an adjective that describes a lack of quality or resources, which does not fit the context of causing a state of uninhabitability.
• expensive: 'Expensive' is an adjective that refers to high cost, which is irrelevant to the action of making something uninhabitable.
• escape: 'Escape' is a verb that refers to getting away from a situation, which does not fit the context of making the countryside uninhabitable.

Correct answer: uninhabitable

Explanation: The adjective 'uninhabitable' describes a state where a place cannot be lived in. This fits grammatically and contextually, as it describes the condition of the countryside after the mud volcano's impact.

Meaning: 'Uninhabitable' means not suitable for living in; unable to support human life.

Wrong options:

• poor: 'Poor' is an adjective that describes a lack of quality or resources, which does not accurately describe the state of being uninhabitable.
• expensive: 'Expensive' is an adjective that refers to high cost, which is irrelevant to the condition of the countryside.
• triggered: 'Triggered' is a past participle that indicates the action of causing something to happen, but it does not describe the state of the countryside.
• started: 'Started' is a simple past verb that indicates the beginning of an action, which does not fit the context of describing a state.
• render: 'Render' is a verb that means to make or cause to become, but it does not fit as a descriptor of the countryside's condition.

Correct answer: exploratory

Explanation: The adjective 'exploratory' describes the type of gas well that was being investigated. It fits grammatically as it modifies 'gas well' and provides context about the nature of the drilling.

Meaning: 'Exploratory' refers to something intended for investigation or examination.

Wrong options:

• triggered: 'Triggered' is a past participle that indicates the action of causing something to happen, which does not describe the type of gas well.
• started: 'Started' is a simple past verb that indicates the beginning of an action, which does not fit as a descriptor of the gas well.
• poor: 'Poor' is an adjective that describes a lack of quality or resources, which does not relate to the type of gas well.
• expensive: 'Expensive' is an adjective that refers to high cost, which is irrelevant to the description of the gas well.
• render: 'Render' is a verb that means to make or cause to become, which does not fit as a descriptor of the gas well.

Correct answer: escape

Explanation: The verb 'escape' fits grammatically as it indicates the action of the hot, high-pressure water moving away from the well. This aligns with the context of the sentence, describing the process of the mud volcano.

Meaning: 'Escape' means to break free from confinement or control.

Wrong options:

• triggered: 'Triggered' is a past participle that indicates the action of causing something to happen, which does not fit the context of water moving away.
• started: 'Started' is a simple past verb that indicates the beginning of an action, which does not fit the context of water moving away from the well.
• poor: 'Poor' is an adjective that describes a lack of quality or resources, which does not relate to the action of water escaping.
• expensive: 'Expensive' is an adjective that refers to high cost, which is irrelevant to the action of water escaping.
• render: 'Render' is a verb that means to make or cause to become, which does not fit the context of water moving away.