You Are Running an Experiment in Calf Serum,which Cannot Be

You are running an experiment in calf serum,which cannot be autoclaved because proteins essential to your protocol will be denatured.  You decide to filter sterilize the serum since the 0.22μm filter is small enough to block any bacteria that may contaminate your tissue culture.  The success of this procedure hinges on the fact that ________.

A) the presence of viruses in your serum is inconsequential to your experiment
B) some of the bacteria will still be allowed to filter through
C) viruses,as well as bacteria,will also be blocked by the 0.22μm pore size
D) the proteins in the serum are also blocked by the pore size