Answer: C) 15
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Step-by-step explanation:
I recommend opening up Excel or any similar spreadsheet program.
Along the top are A,B,C,D,...
Along the left side are 1,2,3,4,...
Cell B1 is the starting cell and we stop at cell D5
What happens is that a rectangle is formed. The first column goes from B1 to B5. The next column over is C1 to C5. The third and last column starts at D1 and goes to D5
There are 5 items in each column, and 3 columns, which gives 5*3 = 15 items total.