Steps for germplasm characterization involve

The correct options are
A testing crops under different environmental conditions
B biochemical and molecular characterization
C checking for disease resistance
Germplasm characterization is the recording of distinctly identifiable characteristics, which are highly heritable.

It starts with growing the crops in fields under suitable conditions and under protection.
They are then tested under various stressful environmental conditions such as drought, salinity, pathogens, etc. to determine if they possess resistance to these conditions. Apart from this field characterization, biochemical characterization and molecular characterization is also carried out in the laboratories.

Thus, through intensive field and laboratory screening, a wide range of sources with desirable traits are identified.