Readable code 1. is written in large font.
2. is written neatly in straight columns.
3. is easy to understand and useful to other programmers working with the code.
4. is password protected so that only authorized programmers can access it.

Readable code is easy to understand and useful to other programmers working with the code, or C on Edge.

Explanation:

It's in the notes on edge in the "Readible Code" section

answer; i believe the correct answer is (a) all trenches must have access/egress;