Question

What caused many people in the urban middle class to oppose Díaz’s dictatorship and support a political revolution?

Answer 1

The need for a democratic government.

They wanted democracy and that caused many people in the urban middle class to oppose Diaz's dictatorship and support a political revolution. 

Good luck :)

Answer 2

They wanted democracy and that caused many people in the urban middle class to oppose Diaz's dictatorship and support a political revolution.