There's a bunch of examples.
For example, hairlines. A widow's peak is a dominant trait over a straigh hairline.
Or dominant hand type. Right hands are dominated over left hands.
Or hair types. Curly hair dominates straight hair.
If you google it, you'll get a lot more examples.
The correct option is this: HAS THE CLAIM BEEN TESTED NUMEROUS TIMES BY MORE THAN ONE SCIENTISTS.
For a claim to be accepted has been valid in the science world, it must have been tested several times by many scientists who obtain the same results. Having a uniform result about a phenomenon is usually considered an important factor when examining the validity of a claim.
Metals, non metals, and metalloids
Explanation:
c a mixture is the answer