Answer:
b. pumice
Step-by-step explanation:
Vesicular texture of rock means the rock has many cavities in all the layers of the rock. Pumice is a soft rock which is the powdered form of volcanic rock which has vesicular texture.
The composition of the pumice rock is commonly formed of silica or felsic. They can be rhyolitic, dacitic, andesite, pantellerite, phonolite, trachyte in composition.
Hence, the rock being described here is pumice.