Scientists were told about the blob so that they could study it.
Answer: Option C.
Explanation:
Blob is a drop of a thick liquid kind of a substance which is very thick in it;s nature and formation. It is a vicious kind of a substance which does not have clear substances in it's formation which can be studied easily.
Since it has been told in the question that the national weather service meteorologists have seen some kind of blob on their radar screen, it is important that the scientists must be informed about it so that they can study about it and take any further steps or precautions required.