Meaning: A 'backpack' is a bag carried on the back, typically used for transporting supplies.

Wrong options:

• waterproof: 'Waterproof' is an adjective describing something that resists water, but it does not fit as a noun in this context.
• lightweight: 'Lightweight' is an adjective that describes something that is not heavy, but it does not serve as a noun and is not appropriate here.
• compass: 'Compass' is a noun that refers to a navigational instrument, which does not fit as the primary item for carrying supplies.
• hiking: 'Hiking' is a gerund that describes the activity of walking in nature, but it does not fit as a noun for carrying supplies.
• breathable: 'Breathable' is an adjective that describes materials that allow air to pass through, which does not fit as a noun in this context.
• sturdy: 'Sturdy' is an adjective that describes something strong and durable, but it does not fit as a noun.

Correct answer: hiking

Explanation: The term 'hiking' is an adjective that describes the type of boots needed for the activity. It fits grammatically as it modifies the noun 'boots' and contextually as it specifies the purpose of the boots.

Meaning: 'Hiking' refers to the activity of walking in nature, and in this context, it describes boots designed for that purpose.

Wrong options:

• waterproof: 'Waterproof' is an adjective that describes something resistant to water, but it does not specify the type of boots needed for hiking.
• backpack: 'Backpack' is a noun referring to a bag, which does not fit as a descriptor for boots.
• lightweight: 'Lightweight' is an adjective that describes something not heavy, but it does not specifically indicate the type of boots suitable for hiking.
• compass: 'Compass' is a noun that refers to a navigational tool, which does not relate to the type of boots needed.
• breathable: 'Breathable' is an adjective that describes materials allowing air to pass through, but it does not specify the type of boots for hiking.
• sturdy: 'Sturdy' is an adjective that describes strength, but it does not specifically indicate the type of boots needed for hiking.

Correct answer: waterproof

Explanation: The word 'waterproof' is an adjective that describes the jacket's ability to resist water. It fits grammatically as it modifies the noun 'jacket' and contextually as it highlights the importance of staying dry in unpredictable weather.

Meaning: 'Waterproof' means that something is designed to prevent water from entering or affecting it.

Wrong options:

• backpack: 'Backpack' is a noun referring to a bag, which does not fit as a descriptor for a jacket.
• lightweight: 'Lightweight' is an adjective that describes something not heavy, but it does not indicate the protective quality needed for a jacket in wet conditions.
• compass: 'Compass' is a noun that refers to a navigational tool, which does not relate to the type of jacket needed.
• hiking: 'Hiking' is a gerund that describes the activity, but it does not fit as a descriptor for a jacket.
• breathable: 'Breathable' is an adjective that describes materials allowing air to pass through, but it does not indicate the waterproof quality required for a jacket.
• sturdy: 'Sturdy' is an adjective that describes strength, but it does not specifically indicate the waterproof quality needed for a jacket.

Correct answer: compass

Explanation: The term 'compass' is a noun that refers to a navigational instrument. It fits grammatically as the subject of the sentence and contextually as it is essential for navigation in unfamiliar trails.

Meaning: A 'compass' is a device used for determining direction, which is crucial for navigation.

Wrong options:

• waterproof: 'Waterproof' is an adjective that describes something resistant to water, but it does not fit as a noun for navigation.
• backpack: 'Backpack' is a noun referring to a bag, which does not fit as a navigational tool.
• lightweight: 'Lightweight' is an adjective that describes something not heavy, but it does not fit as a noun for navigation.
• hiking: 'Hiking' is a gerund that describes the activity, but it does not fit as a noun for navigation.
• breathable: 'Breathable' is an adjective that describes materials allowing air to pass through, which does not fit as a noun for navigation.
• sturdy: 'Sturdy' is an adjective that describes strength, but it does not fit as a noun for navigation.