Answer:

The correct answer is option 'D', Bear.

Explanation:

The sentence describes a situation where someone or something is hiding behind a tree and then runs deeper into the forest. To determine the correct answer, we need to analyze the characteristics of each animal mentioned and see which one aligns with the given description.

Lion:
- Lions are typically found in grasslands and savannas, not forests.
- They are not known to hide or run away from potential threats.
- Therefore, a lion is unlikely to be the correct answer.

Cow:
- Cows are domesticated animals and are not typically found in forests.
- They are not known for hiding or running away from potential threats.
- Therefore, a cow is unlikely to be the correct answer.

Wolf:
- Wolves are known to live in forests and can hide behind trees.
- However, they are social animals and are more likely to travel in packs rather than being solitary.
- Additionally, the sentence does not mention any other wolves, suggesting that the animal being described is alone.
- Therefore, a wolf is unlikely to be the correct answer.

Bear:
- Bears are known to inhabit forests and can hide behind trees.
- They are solitary animals and are capable of running away from potential threats.
- Bears are often associated with forests and are a common animal found in wooded areas.
- Therefore, a bear is the most likely correct answer based on the given description.

In conclusion, the correct answer is option 'D', Bear, as it aligns with the description provided in the sentence.