Answer:
9
Step-by-step explanation:
Since we want the fewest number of groups possible, we need to maximize the number of people in each group. Since there can be a maximum of four people in each group, we can have a maximum of [tex]\left\lfloor \frac{35}{4}\right \rfloor=8[/tex] groups of four. The final three students can form the last group, hence the smallest number of groups possible is [tex]8+1=\boxed{9}[/tex]
