The answer is c or a because it definitely doesn’t pass through a vacuum the fastest
Hey there
<span>The first step is to carefully read every single word of the question and answers,keeping in mind that the some small detail can affect the answer.
You should also pay great attention to negative words and prefixes. Words such as "un" can make your answer wrong if unread properly. If an event is "unlikely to happen," that means it is most likely an occurrence.</span>
Answer:
Physical characteristics.
Explanation:
She knew what type of birds they were based on their physical characteristics.
She didn't see their nests, or see them eat, and she didn't test and analyze their genetics, so a is the correct option.
