Final answer:
To resolve flagella with a diameter of about 1 nm, the maximum wavelength that can be used is 0.5 nm, which is the smallest wavelength provided that is less than 1 nm.
Step-by-step explanation:
To resolve flagella with a diameter of about 1 nm, we must consider the principle that to resolve a detail, the maximum wavelength of light used must be smaller than the detail itself. Therefore, the answer would be the smallest wavelength that is less than the size of the flagella.
The options provided are A) 0.2 nm, B) 0.5 nm, C) 1.0 nm, and D) 2.0 nm. Since we need a wavelength smaller than the flagella size (< 1 nm), the maximum wavelength that can resolve flagella would be B) 0.5 nm, as it is the smallest wavelength provided that is less than 1 nm.
The resolving power of a microscope depends on the wavelength of the incident radiation and the diameter of the aperture. In this case, the diameter of the flagella is provided as 1 nm. To resolve the flagella, we need a microscope with a resolving power equal to or greater than the diameter of the flagella. The maximum wavelength that can be used to resolve the flagella is 0.2 nm (option A).