Six friends, including Doğa and Duru, came to visit Defne's house. Defne randomly gave gifts to two of these friends.
According to this, what is the probability that Defne gave a gift to at least one of Doğa and Duru?
A) $\frac{2}{3}$
B) $\frac{3}{5}$
C) $\frac{4}{5}$
D) $\frac{8}{15}$
E) $\frac{11}{15}$