16) C

Let us calculate the number of tiles on the floor = 15 x 10 = 150 tiles

Let us divide the floor into 6 sections. Each section looks like this:

In each section, there are 25 tiles.

5 completely white tiles = 0% black

4 completely black tiles = 100% black x 4 = 4

4 one-quarter black tiles = 25% black x 4 = 1

12 half-black tiles = 50% black x 12 = 6

4+1+6 = 11

Percentage black = (11/25) x 100 = 44%

Since this section represents the whole diagram, we can say that the entire floor is 44% black.