Textual evidence is sentences used to confirm the arguments presented by the author of the text.
It is not possible to know the text to which your question refers, for this reason, it is not possible to show you the evidence that the author used to support the idea that removing iodine from table salt can cause damage. However, I will show you how to find this evidence.
First, you must know that the argument is an opinion that the author presents. In this case, when the author claims that removing the iodine from the table salt is harmful, this author is showing an opinion, that is, an argument.
This author needs to prove this argument with evidence, that is, with facts and information that show that this argument is correct.
To find this evidence you must:
Read the entire text.
Re-read the text and identify the paragraph where the author presents the argument about iodine.
Identify in this paragraph what are the data, facts and information that confirm this argument and show that the author is correct.
You can find more information about this at the link below:
Hey do you love gummy bears? Well great I have an infinite supply running through my household water supply. Now some people say that showering in gummy bears makes you sticky and nasty but I argue that it makes me smell sweet, deliciou, and it brightens my day and makes me feel colorful yet artistic. You may hate gummy bears but in times like these we need a little color and a lil sweetness. Or a friendly lil bear that you can bite the head off of. So wether you like gummy bears or not I will continue to shower in them for that smidgen of brightness that we need in this world! OwO