I would go with B) Nerves in the finger detect stimuli and send the message to the brain.
Answer:
El músculo estriado cardiaco es una forma especializada de músculo estriado, conforma la pared del corazón, cuya contracción rítmica es involuntaria.
Water (H
2O) is a polar inorganic compound that is at room temperature a tasteless and odorless liquid, which is nearly colorless apart from an inherent hint of blue. It is by far the most studied chemical compound and is described as the "universal solvent" [17][18] and the "solvent of life".[19] It is the most abundant substance on Earth[20] and the only common substance to exist as a solid, liquid, and gas on Earth's surface.[21] It is also the third most abundant molecule in the universe.[20]
Answer: B. Water breaks down into oxygen molecules for respiration.
Water is the required for photosynthesis, a process by which plants (terrestrial and aquatic) makes their food by utilizing water as a reactant to produce oxygen and glucose as product. The glucose act as a source of energy for conducting various metabolic processes in plants but oxygen is released in the air.

This oxygen is necessary for terrestrial and aquatic animals for respiration. Therefore, water breaks down into oxygen by the process of photosynthesis, hence water plays important role in respiration in living beings.
I believe it is a Pure Substance