What are the characteristics of stratus clouds?

Stratus clouds are characterized by their very thin, low to the ground formation and gray appearance. These clouds typically cover the sky in a uniform layer, leading to overcast conditions. The low altitude of stratus clouds means they are often found at or below about 2,000 meters (6,500 feet) and usually lack the vertical development seen in other cloud types, making them appear more like a blanket or layer.

Their gray color is indicative of their moisture content, which can result in light rain or drizzle, particularly as they thicken. This contrasts with other cloud types that are more vertically oriented or have brighter characteristics due to sunlight reflection. For example, fluffy and towering clouds usually describe cumulus or cumulonimbus varieties, while high-altitude clouds composed of ice crystals are typically cirrus. Layered clouds can belong to various types, but the specific traits of stratus — particularly their thickness and low placement — are what make option B the most accurate choice.