Final answer:
Foraminifera, or forams, are protistans with protective shells made from minerals and organic materials, known as tests, and utilize pseudopodia for movement and feeding.
Step-by-step explanation:
The category of protistans that possesses a protective shell made from a combination of minerals and organic materials and often exhibits an oddly shaped structure is Foraminifera (Option A). The forams, or foraminiferans, are known for their porous shells, called tests, which are built from various organic materials and typically hardened with calcium carbonate. Foraminiferans are utilized in environmental monitoring as they are good indicators of pollution and changes in global weather patterns. These organisms move and feed by extending pseudopodia through the pores in their shells. Foraminifera may also have photosynthetic algae living within their shells, which they can use for nutrition.