Answer: C) A child fear a mysterious elderly neighbor, but he learns that she is actually funny and kind when she helps him find his lost dog.
Explanation: From the given options, the story that best illustrates the themes of misjudging others and the happiness of meeting new friends is the corresponding to option C, A child fear a mysterious elderly neighbor (the child is misjudging the neighbor), but then he learns that she is actually funny and kind when she helps him find his lost dog (this represents the happiness of meeting new friends).