Solve the Division Problem: How Many Cookies Did Sarah Buy to Share Equally?

To solve this problem, we'll follow these steps:

• Check each multiple-choice option to see if it is divisible by 4 using the last two digits of each number.

Let's apply the solution:

Choice 1: $316$
The last two digits are $16$. Check divisibility by 4: $16 \div 4 = 4$, exactly divisible.

Choice 2: $315$
The last two digits are $15$. Check divisibility by 4: $15 \div 4 = 3.75$, not exactly divisible.

Choice 3: $314$
The last two digits are $14$. Check divisibility by 4: $14 \div 4 = 3.5$, not exactly divisible.

Choice 4: $313$
The last two digits are $13$. Check divisibility by 4: $13 \div 4 = 3.25$, not exactly divisible.

Therefore, the solution to the problem is $316$, as it is the only number that is divisible by 4.