Arrange the following parts of a sentence in the correct order and mark the correct option.
A. found his copy
B. of the bicycle
C. he fished around until he
D. at the Byrne home.
E. magazine he'd seen

The correct option is CABED.

To arrange the sentence fragments into a coherent and grammatically correct sentence, let us analyze each part and its connection to the others:

1. C. he fished around until he serves as an ideal starting clause, introducing the subject ("he") and an ongoing action ("fished around until he...").
2. Following "until he", we need a verb in the past tense to complete the clause. A. found his copy naturally follows, forming "he fished around until he found his copy".
3. Next, we need to specify what he found a copy of. Part B. of the bicycle connects directly to "copy", forming "copy of the bicycle".
4. Part E. magazine he'd seen qualifies "bicycle", forming the complete noun phrase "bicycle magazine he'd seen".
5. Finally, part D. at the Byrne home. provides the prepositional phrase indicating the location where he had seen the magazine.

Combining these parts in order (C → A → B → E → D), we get the full, meaningful sentence:
"He fished around until he found his copy of the bicycle magazine he'd seen at the Byrne home."

Therefore, the correct sequence is CABED.