Meaning: 'Flush out' means to remove or eliminate something, especially toxins from the body, often through urination or sweating.

Wrong options:

• push through: This phrase typically means to continue despite difficulties, which does not relate to the context of removing toxins.
• pull in: This phrase suggests bringing something closer or attracting, which is not relevant to the act of detoxification.
• take up: This phrase generally means to occupy space or time, which does not fit the context of eliminating toxins.

Correct answer: age

Explanation: The word 'age' is the most relevant option as it directly relates to how hydration needs can vary among individuals. It fits grammatically as a noun that complements the phrase 'depending on your' and is contextually appropriate since hydration needs can change with age. The other options do not have the same relevance to hydration needs.

Meaning: 'Age' refers to the length of time that a person has lived, which can influence their hydration requirements.

Wrong options:

• height: While height can affect hydration needs, it is not as directly relevant as age in this context.
• colour: This option is unrelated to hydration needs and does not fit contextually or grammatically.
• shape: Similar to colour, this option does not pertain to hydration needs and is irrelevant in this context.

Correct answer: hydration

Explanation: The term 'hydration' is the most suitable choice as it directly refers to the process of maintaining adequate fluid levels in the body. It fits grammatically as a noun that completes the phrase 'overall' and is contextually appropriate since the passage discusses water intake. The other options do not specifically relate to fluid intake.

Meaning: 'Hydration' refers to the process of providing adequate water to the body to maintain health and function.

Wrong options:

• nutrition: While nutrition is important, it does not specifically refer to water intake, making it less relevant in this context.
• digestion: This term relates to the process of breaking down food, which is not the focus of the passage regarding water intake.
• circulation: Although circulation is important for health, it does not directly relate to the concept of water intake as hydration does.

Correct answer: slightly

Explanation: The word 'slightly' indicates a small degree of dehydration, which fits grammatically as an adverb modifying 'dehydrated' and contextually aligns with the idea that feeling thirsty is an early sign of dehydration. The other options do not convey the same subtlety of meaning.

Meaning: 'Slightly' means to a small extent or degree, indicating that the person is not severely dehydrated yet.

Wrong options:

• barely: This implies an even lesser degree than 'slightly,' which does not accurately reflect the context of feeling thirsty.
• not: This negation does not fit grammatically or contextually, as it contradicts the idea of experiencing thirst.
• significantly: This suggests a large degree of dehydration, which is not appropriate given the context of the passage.