Correct option is A
When fabricating ICs, the method used to grow silicon dioxide depends on the required thickness and quality:Wet oxidation∙ Much faster oxidation rate than dry oxidation∙ Suitable for thick SiO2 layers (> 1 μm)∙ Produces lower-quality oxide with higher interface state density∙ Commonly used where oxide quality is not critical (field oxides)Dry oxidation∙ Produces high-quality SiO2∙ But growth rate is slow, not suitable for thick layersThus, to achieve fast growth of thick oxide while tolerating poorer interface quality, wet oxidation is preferred.