Introduction:
The given lines are from the poem "The Village Blacksmith" by Henry Wadsworth Longfellow. The poet describes the bright topaz denizens, which refers to the bees, in a world of green. These bees are not afraid of men who are beneath the tree and move confidently in a chivalric manner. The question asks why these bees are not afraid of men, and the correct answer is that they are strong and powerful.

Explanation:
The bees in the poem are depicted as confident and fearless creatures. The reason why they are not afraid of men can be understood through the following points:

1. Strength and Power:
The bees are described as bright topaz denizens, suggesting their vibrant and powerful nature. Bees are known for their strength and ability to work together as a collective. They have the capacity to protect themselves and their hive. Their stingers are a potent defense mechanism against potential threats. Therefore, the bees' strength and power make them fearless in the face of men.

2. Chivalric Certainty:
The poem mentions that the bees pace in sleek chivalric certainty. This line implies that the bees move with a sense of purpose and confidence. Bees are highly organized social insects that follow a strict hierarchy within their colony. They have specific roles and responsibilities, and they work together harmoniously. This chivalric certainty suggests that the bees trust in their collective abilities and are not easily intimidated by external factors, including men.

3. Lack of Awareness:
While the poem does not explicitly state this, it is possible to interpret that the bees may be unaware of the presence of men. Bees are primarily focused on their tasks, such as gathering nectar, pollinating flowers, and building their hive. They may not perceive men as a direct threat or disturbance to their activities. Therefore, their lack of awareness about the presence of men contributes to their fearlessness.

Conclusion:
The reason why the bees in the poem are not afraid of men is that they are strong and powerful creatures. They possess the ability to defend themselves and their hive. Additionally, their sleek chivalric certainty and lack of awareness about the presence of men contribute to their fearlessness. The bees' confidence and resilience in the face of potential threats symbolize their unwavering dedication to their work and their collective strength as a community.