What is missing from the counting mat? The count is shown in A, B, or C.
Let’s look at the counting mat. Here, we have one counter, two counters, three counters. Here, we have a number four, but no counters. Are these the missing counters? There’s one, two, three. So these are not the missing counters.
Let’s count these counters: one, two, three, four. So this is the missing group of counters from the counting mat.