The sequence S_{1}, S_{2}, S_{3}, \ldots, S_{10} has the property that every term beginning with the third is the sum of the previous two. That is,
S_{n}=S_{n-2}+S_{n-1} \text { for } n \geq 3
Suppose that S_{9}=110 and S_{7}=42. What is S_{4} ?
Answer Choices
A. 4
B. 6
C. 10
D. 12
E. 16