This situation is analogous to a double replacement reaction. A double-replacement reaction occurs when parts of two ionic composites are exchanged, making two new composites. One characteristic of this kind of reaction is that there are two compounds as reactants and two different compounds as products. So, in this case we can relate with it because there are two new couples with the same members that formed the previous couples.
The answer is D. There on the monitor screen was a big smiley face!. Because an independent clause is a sentence that's able to be by itself and make sense,
