Incorrect+Sound

=Woops! It looks like you were trying to signal the puffins and you made the wrong sound. As a result, a swarm of other birds has landed on the rocks. There is no way we are going to be able to make any observations while they are here. = = =

=Answer the question below to shoo them off and to try again. = = =

=Which of the following is a correct definition of estuary? = = a) an area where a river (freshwater) and the ocean (saltwater) mix = = b) an area where a river (saltwater) and the ocean (saltwater) mix = = c) an area where to rivers (freshwater) mix = = d) an area where a river (freshwater) and the ocean (freshwater) mix =