How would the formation of bacterial colonies be affected if bacterial cells did not contain pili?

Pili is the protein structure formed outside the cell wall of bacteria. The main function of pili is the bacterial cell attachment. It facilitate bacteria to attach at a substrate to derive nourishment. Also, helps in sexual reproduction in bacteria by forming the sex pili between two bacterial cells and allows the exchange of genes between these cells. Bacterial colonies can form on aquatic as well as in terrestrial habitat. Bacteria to hold the substrate properly pili is required. There are chances that bacterial colonies wash away from their substrate or get removed because of external environmental consequences. Therefore, absence of pili will affect colony formation.  

i think that c)gold was found there

but i am not sure