Answer:
Option A, Cirrus
Explanation:
Cirrus are thin clouds found at greater heights (some 25000 feet above the ground). They are made up of super cooled water and generally represents fair weather.
While Stratus cloud leads to rain when it gets warm and snow when its gets cold, so the weather is not fair when there are Stratus cloud in the sky
Nimbus cloud also causes rain, snow or other form of extensive precipitation and hence they are also not responsible for producing fair weather condition
Altonimbus is a mid level cloud which also causes precipitation in some or the other form.
Hence option A, Cirrus is the correct answer among all given option
