Correct Answer: D

Rationale: The correct answer is D. The sources of water intake include drinking fluids, consuming water from the food we eat, and water from metabolic processes. Water intake is not solely from the liquids we drink but also from the water content present in the food we consume and the water produced during metabolic processes such as cellular respiration. Therefore, option D is the correct answer as it covers all the sources of water intake. Options A, B, and C alone do not encompass all the sources of water intake, making them incorrect choices.

Correct Answer: D

Rationale: The correct answer is 'Electrolyte.' Electrolytes are substances that dissociate into ions when dissolved in water. Intracellular fluid, interstitial fluid, and plasma are not substances that dissociate into ions in a water solution. Intracellular fluid is the fluid inside cells, interstitial fluid is the fluid between cells, and plasma is the liquid component of blood. These choices do not dissociate into ions in a water solution, unlike electrolytes.

Correct Answer: B

Rationale: The correct answer is 'aldosterone.' Aldosterone is the hormone that reduces the amount of water in the body by increasing the reabsorption of sodium and water from the kidney tubules. ANH (atrial natriuretic hormone) actually works to increase the excretion of sodium and water by the kidneys, leading to a reduction in blood volume and pressure. ADH (antidiuretic hormone) works to increase water reabsorption by the kidneys, thereby increasing blood volume. Therefore, choices A (ADH) and D (ADH and aldosterone) are incorrect in the context of reducing the amount of water in the body.

Correct Answer: B

Rationale: The correct answer is 'Intracellular fluid.' Intracellular fluid refers to the fluid contained within the cells, constituting a significant portion of the body's total water content. Choices A, C, and D are incorrect. Plasma is the liquid component of blood outside the cells, interstitial fluid is the fluid surrounding cells in tissues, and the combination of plasma and intracellular fluid is not the specific term for the fluid inside the cell.

Correct Answer: D

Rationale: Intracellular fluid contains phosphate ions and protein molecules as essential anions. Phosphate ions play a crucial role in various cellular processes, including energy transfer. Proteins, being large molecules with negative charges, also contribute significantly to the negative ion concentration within cells. Chlorine is primarily an extracellular anion and is not as prominent as phosphate ions and proteins within intracellular fluid, making it a less important negative ion in this context. Therefore, the correct answer is D because both phosphate ions and protein molecules are crucial negative ions in intracellular fluid.