The best scientific question that could explain the phenomenon observed by the scientist would be B. What nutrients that moths need are in elephant tears? This question focuses on understanding the relationship between the moths and elephants, specifically why the moths are attracted to and consume the tears, which suggests a nutritional or biological significance.
While the other options are valid inquiries, they do not directly seek to explain the behavior observed in terms of ecological relationships or biological needs. Therefore, option B is the most pertinent for exploring the underlying reasons for this interaction.
However, if you wanted to consider the broader context of the ecological interaction, option D. all of these could also be seen as valid since all of those questions could lead to a more comprehensive understanding of the situation.