Answer:
Oxygen first and Silicon Second
Explanation:
Answer:
A,Development
Explanation:
to cause change to a nation is for it to develop
I know this for 100% it is A. they're convenient , I know this one for sure 100% positive hope it helps
The threat to validity that is likely to occur in the scenario above is Selection Bias.
<h3>What is Selection Bias?</h3>
This occurs when a researcher has control and intentionally chooses those who are going to be researched, observed, or studied. To eliminate this bias, the scientist must ensure that the sample population is selected very randomly.
Other threats to validity are:
- History
- Maturation
- Attrition
- Social Interaction
- Instrumentation
- Testing
- Regression to the mean, etc.
Please see the link below for more about Threat to Validity:
brainly.com/question/4168290
