In this question some words are incorrectly written; here is the complete and correct question:
Which question would be the best high-level scientific question?
A. How many giraffes live in Africa?
B. Who made the first microscope?
C. How long ago did dinosaurs live on Earth?
D. Does the amount of salt in water affect the temperature at which it boils?
The answer to this question is D. Does the amount of salt in water affect the temperature at which it boils?
Step-by-step explanation:
Scientific questions focus on testing a possible explanation (hypothesis) about a phenomenon or helping scientists to better understand a phenomenon. Moreover, because these are part of the scientific method, high-level questions can only be answered through experimentation or observation and they usually contain two or more variables.
These features occur only in option B because this question can only be answered through experiments; for example, by boiling water with different amounts of salt and recording the boiling temperature; this helps scientists to understand how salt affects certain properties and this includes two variables (the amount of salt vs boiling temperature.)