Has an error at the cellular level
Tissue by itself is defined as a group of cells working together to perform a specific function. The first option, "contains more than one type of tissue" is the definition of an organ.
If a tissue is made up of cells, then diseased tissue would have something wrong with the cells that make it up. Hence option two of "has an error at the cellular level" is the best way to describe diseased tissue.
A.Contains more than one type of tissue..(sorry if I'm wrong T~T)