Read the excerpt from How the Other Half Lives by Jacob Riis. One, two, three beds are there, if the old boxes and heaps of foul straw can be called by that name; a broken stove with crazy pipe from which the smoke leaks at every joint, a table of rough boards propped up on boxes, piles of rubbish in the corner. The closeness and smell are appalling. How many people sleep here? The woman with the red bandanna shakes her head sullenly, but the bare-legged girl with the bright face counts on her fingers—five, six! "Six, sir!” Six grown people and five children. "Only five,” she says with a smile, swathing the little one on her lap in its cruel bandage. There is another in the cradle.

Based on this excerpt, what was one of the most significant problems of tenement living?

crime
disease
overcrowding
unemployment