What is the name traditionally given to a semaphore that enforces the concept of mutual exclusion?

The worst scenario for insertion sort is

a. 9 8 7 6 5 4 3 2 1 b. 1 9 2 8 3 7 4 6 5 c. 8 2 6 4 5 3 7 1 9 d. 5 6 3 8 9 2 1 7 4

____ are represented in the low third of the grayscale range.

A. Midtones B. Highlights C. Tones D. Shadows