I'm doing research aims to asses the inhibitory activity of an extract against bacteri (Streptococcus, sp),

I prepared the extract in different concentration (25%, 50% and 75%)

I prepared bacterial suspension equal to 0,5 macfarland

suspension strek to MHA according to CLSI recomendation

I will perform these prosedur by disc diffusion method in TRIPLO REPETITION,

for these workflow :

wich one the right concept to perform a triplo repetition test in disc diffussion test?