The correct placement for the comma in this sentence is this: a. We found a wiggling, adorable puppy!
The best way to place the comma in the sentence is to insert it after the first adjective which is wiggling. This helps the reader see the sequence in the sentence.
So, the option that best explains the placement of the comma and other punctation marks in this sentence is option A which is; We found a wiggling, adorable puppy! The reader will then be able to separate the descriptions from the noun which is the puppy.