Believability Of a speaker is highly dependent on supporting materials for that are

credible

Explanation:

Public speaking refers to the process of communicating the ideas to the live audience by a specific speaker. A group of listeners and a speaker are its main elements. There are various aspects on which a speaker is required to focus while delivering a public speech. The supporting materials for or against the topic that are provided by the speaker helps in building a strong argument before the listeners. Also, the belief in the speaker is established with the credibility of the supporting materials.

the answer is: b: however, that doesn’t mean that the current drought isn’t real.

the answer is actually c   i just got done with the test.