Answer:
D. 60cm²
Explanation:
First, notice how the partially shaded squares fit perfectly into one another (the squares are perfectly cut from corner to corner). Once you match these squares to one another, you can then figure out that they add up to three full squares.
Secondly, measure how many squares there will be in the diagram after adding up the partial squares (resulting in a total of 15).
Finally, calculate the area of one of the squares (2cm x 2cm), which results in 4cm². As you have 15 total squares, multiply 4cm² by that to get the final answer of 60cm².