Multi-choice problem: Choose from the options at the end, and answer how do you do this: to sift flour without a sifter

Select from:
a). Find a strainer and a bowl slightly larger than the strainer. Position the strainer over the bowl with your one hand. Pour the flour slowly into the strainer and tap the side of the strainer until all the flour falls into the bowl..
b). Find a strainer and a bowl slightly smaller than the strainer. Position the strainer over the bowl with your one hand. Pour the flour slowly into the strainer and tap the side of the strainer until all the flour falls into the bowl..
a).