Let \left(a_{1}, a_{2}, \ldots, a_{10}\right) be a list of the first 10 positive integers such that for each 2 \leq i \leq 10 either a_{i}+1 or a_{i}-1 or both appear somewhere before a_{i} in the list. How many such lists are there?

**Answer Choices**

A. 120

B. 512

C. 1024

D. 181,440

E. 362,880