What best explains why the industrial revolution led to larger middle class

One drawback of voluntary trade is that it a.requires two groups to use a common language b.can make one group dependent upon another for necessary goods c.doesn't occur unless there is a shortage of goods for at least one group d.forces groups to rely on themselves to produce all the goods they need

Doing an exit ticket and i need some

Why did england's citizens restore the monarchy after the rule of oliver cromwell?