In a microbiology laboratory, the technician uses heat to sterilise the nutrient solution that is used to grow a fungus. When the heating system broke down, he sterilised the solution by passing it (in a sterile environment) through a sterile filter with a pore size of `0.2` micrometers. when the fungs was grown on the filtered nutrient solution, it stopped growing and looked unhealthy within a few days. which statements is the most likely explanation for the observed effects on the fungus ?

Options

A. The nutrient solution contained a virus.
B. Heating makes the glucose in the nutrient solution more digestible
C. Filering removed one of the larger nutrient molecules
D. The nutrient solution contained a bacterium that was pathogenic to the fungus.

Answer

A

Explanation

The nutrient solution could have contained a virus which passed easily through the sterile filter of pore size of `0.2` micrometer. This caused retarded and unhealthy growth of the fungus.