The correct answer is: sea stars
All animals listed above are invertebrates. One of the characteristic of invertebrates are that they are protostomes with the exception of Echinodermata (sea stars). The difference between protostomes and deuterostomes is in their embryonic development (orgin of mouth and anus).
In protostomes the mouth forms first: the oral end of the animal develops from the first developmental opening. On the other hand in deuterostomes the first opening (the blastopore) becomes the anus, and the oral end of the develops from the second opening.
Humans are also deuterostomes.  
 
        
             
        
        
        
According to Kinsey's sexual behavior study, approximately 21 percent of men and  6 percent of women had sexual intercourse by the age of 16. (Please mark me brainliest! thank you in advance!!)
 
        
             
        
        
        
Is there anything you need help with for this problem? I need to clarify first before answering your question.
        
             
        
        
        
Answer and Explanation:
 A null hypothesisstates that there is no significant difference between specified populations, any observed difference being due to sampling or experimental error.
In order to reject or retain a null hypothesis, compare the P-value to the alpha . If the P-value is less than (or equal to) ,the null hypothesis is rejected in favor of the alternative hypothesis. If the P-value is greater than , the null hypothesis is not rejected.