The reason why the speaker declined to grant product endorsements was that she said that she would have been going beyond science and good scientists are careful not to do this.
This refers to the personal indication or seal of approval that is given to a particular item or a company about something to give it credibility.
Hence, we can see that from the complete text, there is the narration of the product endorsements and why the speaker did not give one because it would go beyond science.
Read more about endorsements here:
https://brainly.com/question/11463115
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