Final answer:
The missing information considering the context provided is 'd. not enough information'. The book excerpt does not specify details about Wally's cycling conditions such as clothing, gear, or the bicycle.
Step-by-step explanation:
Considering the book excerpt provided, the missing information is d. not enough information. The text mentions Wally's attitudes towards cycling, but does not provide specific details on the conditions of his cycling, such as his clothing, gear, or the bicycle itself. Therefore, we cannot determine which specific aspect is being referenced without that context.
The excerpt focuses on a conversation between Venters and another character about their experiences while riding. It touches on Venters's curiosity about the other character's life and their past riding habits. However, the passage does not tie back directly to Wally's cycling specifics, such as clothing or gear, which would help indicate the correct missing piece of information. Consequently, we lack sufficient details to answer definitively.