Julia, Kasia, Susanna, and Helena have their birthdays on March $$1^{\rm st}$$, May $$17^{\rm th}$$, July $$20^{\rm th}$$, and March $$20^{\rm th}$$. Kasia and Susanna were born in the same month. Julia and Susanna were born on the same day of a month. Which of the girls was born on May $$17^{\rm th}$$? ． 
选项为:A:Julia  B:Kasia  C:Susanna  D:Helena  请回答其中一个选项.