Babies, especially those who are at least 4-6 months old, have the tendency to explore objects by touching and holding them, and putting them in their mouth. By this time, it is very important to keep small objects out of their reach so that accidents can be prevented.
Answer:
A and B are the answers.
Explanation:
Believe me I took a test a while ago with this question
One example is using tree rings on a tree to determine the absolute time
Because he was a monk, not a scientist, and his work was not widely published.