To determine the probability that Owen pulls out a yellow pencil from his backpack, we can proceed step-by-step as follows:
1. Determine the Total Number of Pencils:
Owen has three pencils in his backpack, and this is the total number of pencils.
2. Identify the Number of Yellow Pencils:
All three pencils in Owen's backpack are yellow. Therefore, the number of yellow pencils is three.
3. Calculate the Probability:
The probability of an event (in this case, picking a yellow pencil) is defined as the ratio of the number of favorable outcomes to the total number of possible outcomes. Here, the favorable outcome is picking a yellow pencil.
[tex]\[
\text{Probability} = \frac{\text{Number of Yellow Pencils}}{\text{Total Number of Pencils}}
\][/tex]
Substituting the numbers we have:
[tex]\[
\text{Probability} = \frac{3}{3}
\][/tex]
4. Simplify the Fraction:
The fraction [tex]\(\frac{3}{3}\)[/tex] simplifies to 1.
Thus, the probability that Owen will pull out a yellow pencil is 1, which corresponds to the fraction [tex]\(\frac{3}{3}\)[/tex].
Therefore, the correct answer is:
[tex]\[
\boxed{\frac{3}{3}}
\][/tex]
